'Dark satanic Mills' is what some of his colleagues used to call him, and, with that Mephistophelian beard and somewhat steely-eyed and grim-lipped expression, one can see why. Drape a black cloak over his shoulders or drop a white cat on his lap and he would have looked eerily at home as a Moriarty-like crime master or a coolly sadistic Bond villain. His appearance, however, was deceptive, because, behind that sombre exterior, Michael Mills was actually one of the most sharp-witted, enthusiastic and inspirational creative forces in the history of British comedy.

He made things happen. This is not merely to suggest that he signed contracts and flicked switches. He was immersed in every stage of the programme-making process.

He spotted talent, started careers, put together partnerships, turned ideas into things and made people believe in themselves and their projects and their audiences. He could do anything and everything himself, from writing and directing to producing and commissioning, but he also helped many others to do one or another of these things even better than they had thought possible.

He was one of the pioneers of television programme-making in Britain, and then he was one of those who pushed and polished it into maturity. He knew unerringly well when to focus on the small details and when to consider the big picture. He knew when to step in and offer help and when to hold back and leave well alone. He had good taste, great instincts and glorious enthusiasms.

He was, in short, one of the best things that happened to British television in general, and its comedy in particular, throughout its formative years. Think of any outstanding, ground-breaking, exceptionally entertaining BBC TV show from the 1950s to the 1970s, and it will almost certainly owe some element of its existence to the bright and beneficent Mills.

Born in Prestwich, Lancashire, in 1919, he was the son of William Haslam Mills, a distinguished barrister, author and journalist for the Manchester Guardian, and educated at Westminster School and various small and exclusive academies in Germany, France and Switzerland, before joining the BBC in 1938, at the age of nineteen, as a junior production assistant in radio. War put his fledgling career on hold - he would spend six years serving with distinction in the Royal Navy (as well as two-and-a-half years as a liaison officer aboard ships of the Free French forces) - but he re-joined the Corporation in 1947 as a trainee producer/director.

What he was presented with, in those primitive days of television, was effectively a blank canvas on which to paint the kind of picture that he thought audiences might be intrigued to see. There were no real rules yet to dictate what a programme-maker should do, or how they should attempt to do it, and so Mills, along with a handful of his fellow pioneers, was left free to define, through a process of trial and error, the role of a producer and director and the means of making content for television (it was 'a case', he liked to joke self-deprecatingly, 'of the blind leading the short-sighted').

Some young budding programme-makers, finding themselves standing alone in the middle of the BBC's huge, empty and echoey studios, felt overwhelmed by the sheer enormity of the task before them. Mills, on the other hand, saw these cavernous spaces as a cross between a playground and a laboratory, and could not wait to start filling them with his visions.

He introduced the sets, the cameras, the microphones, the lighting and the performers, he moved them all around, and he worked out for himself how best to choreograph them all to benefit what would eventually be seen on the screen. Always active and never passive, the best way to work out the medium's full potential, Mills reasoned, was to keep pushing at it rather than just pondering it.

His main home, once the BBC had started moving its operations from Alexandra Palace to Lime Grove in the early-1950s, was the exceptionally capacious Studio E, which would stage the BBC's most elaborate and spectacular music, variety and drama productions for the rest of the decade. Mills was so thrilled with the vast amount of space that, to mark the start of his residency there (in August 1953), he invented a bit of business for one show just so that he could get the actor Bill Fraser to drive all around the stage in a sports car.

Filming was still quite a physical as well as a technical challenge, because the heat of the huge arc lights was so intense as to cook a TV chef's omelette before he could pour it into a pan (which was one reason why, for a while, the most energetic of studio productions tended to be scheduled well away from the sweltering summer months), and the large and heavy cameras moved frustratingly slowly and awkwardly (he sometimes defied the fire regulations and had a camera stuck in the corridor to stretch out a longer shot), but Mills adored the adrenaline rush that accompanied each session. 'There were no dummy runs,' he would say, 'everything was tried out live in full view of the public, and so one just had to find ways, there and then, to overcome any problems and make it all work.'

The very endearing, and sometimes highly unnerving, thing about Mills in those early and somewhat anarchic days of broadcasting, was his apparent belief that, because he could do something very effectively, just about anyone else, if he liked the cut of their jib, could probably do much the same thing, too. In 1950, for example, when the BBC was still quite short of TV producer/directors, he decided that a friend of his, the up-and-coming actor Ian Carmichael (pictured below), might as well have a go.

'I can get you a fifteen-minute slot in about six weeks' time,' he barked at his startled companion. 'You're only allowed to use one artist.'

The slot to which Mills was referring belonged to a variety series called Starlight. He felt it would be a good start.

Carmichael - as he recalled many years later to Kate Dunn for her book Do Not Adjust Your Set - exclaimed: 'Michael, hold the line. I've never been up in a producer's box in my life, I wouldn't know what to do, I don't know anything about cameras!'

Mills assured him that it would all be fine. He added that, just to ease him into the role, he would assist him for the first rehearsal, and then hover behind him for the second one, before leaving him to it for the actual live transmission.

A still-nervous Carmichael, feeling as though he should at least attempt to repay this show of faith, duly went ahead and booked the singer Petula Clark as his first solo star and arrived at the studio ready for the first rehearsal. He saw that the camera operators were already there, as was the pianist he had hired, and so was Petula Clark. There was no sign, however, of Michael Mills, who apparently had distracted himself - as was his wont - with what was happening on another set. 'Bloody hell!' the novice programme-maker thought to himself.

He waited for half an hour in the hope that his mentor would appear, but then, with everyone looking at him in the expectation of some actual direction, he very reluctantly climbed up the ladder into the production booth and sat down miserably in front of two small monitors. Prompted, much to his immense relief, by an elderly technical assistant who seemed to emerge from out of the shadows like Igor from Frankenstein's workshop, he somehow managed to start moving people around and work out some sort of plan for the performance.

Eventually, just when - his shirt now sticking tightly to him with nervous perspiration - he was about to force himself to run through the same steps again, Mills suddenly burst through the door, smiled and said 'Carry on, keep going!' and then stood silently, puffing up plumes of smoke from his pipe, watching from the back of the booth. Unsure, by this stage, quite how to feel about this mute presence perched behind him, Carmichael went ahead, hesitantly, repeating the process.

When it was over, instead of Mills sitting down and explaining how to do it 'properly', he once again startled Carmichael by merely marching straight off out of the door, turning as he departed to boom back brightly at his latest protégé: 'Right, that's fine, I'll give you a ring tonight to let you know how it went!'

That was how Michael Mills (with the invaluable support of his long-suffering but deeply devoted assistant, Yvonne Littlewood) tended to get things moving in those formative years of TV production. 'He was a goer was Michael, a real whirlwind, he'd boundless energy,' Littlewood would recall with great affection. 'He frightened me to death!'

He was, it is fair to say, a mercurial man. There was often, however, a method to his moods.

Retaining more than a trace of the rather brusque and imposing manner of the Naval officer that he once had been (a few of his more irreverent assistants were known to wink and whisper 'Hornpipe' to alert each other as the sound of his footsteps started echoing down the corridor), he was not afraid to shout and snap if he thought that people needed it. He was, however, also capable, on occasion, of putting his arm around a shoulder and offering some calm and constructive advice.

It was thanks at least in part to him that such comic talents as Terry-Thomas, Richard Hearne, Benny Hill, Norman Wisdom, Reg Varney, Avril Angers, Michael Bentine, Jon Pertwee, Harry Secombe, Jimmy Jewel and Ben Warriss, Jimmy Edwards and Arthur Askey were eased on to the TV screen, along with countless other figures from drama, music, variety and even current affairs (he helped launch and develop Panorama). He also devised numerous formats, nurtured series that ranged from sketch shows to soaps, staged some of the earliest studio spectaculars (with as many as one hundred-and-five separate sets per programme), trained a remarkable number of technical specialists and won the BBC some of its most prominent and positive coverage of the post-war era.

Having packed so much into his first eight years in television, and feeling ready for a change, he resigned in 1955 to work in the theatre for the Howard & Wyndham chain in Scotland (while picking and choosing small screen projects as a freelance both for the BBC and the newly-formed ITV companies), before coming back to the Corporation three years later, and was then seconded to help found the Lebanese Television Service in Beirut. He returned to Britain at the start of the Sixties to work as a freelance before re-joining the BBC once again in 1964.

Plunging himself back into the heart of the production process, he quickly became one of the most industrious - and probably the most versatile - programme-makers of the period, responsible for output ranging from a Stanley Baxter sketch show to a special programme marking the ninetieth birthday of Sir Winston Churchill. The typical Michael Mills production was notable for the boldness of its ambition, the high quality of its constituent parts and the polish of its presentation. More so than any of his peers, he knew how to deliver the 'wow' factor.

He also knew how to handle wit, and, from 1965 onwards, he would demonstrate this by beginning what would become a long, very successful and extremely satisfying association with the work of P.G. Wodehouse, overseeing The World Of Wooster (1965-7), Blandings Castle (1967), Uncle Fred Flits By (1967) and Wodehouse Playhouse (1976). Everything about that first series - the casting (which saw him select Ian Carmichael as Bertie Wooster and Dennis Price as Jeeves, pictured together above), the scripts (adapted by Mills, in collaboration with Richard Waring, from the original stories), the design and the technical input - was judged so well, with such care and good taste, that it won the admiration and respect not only of the critics (who applauded its selection as the BBC's entry for the annual Golden Rose of Montreux Festival) but also of P.G. Wodehouse himself, who (having initially expressed his hope that it would never be attempted) considered it an impressively effective visualisation of his writing.

Mills was similarly successful in translating A. P. Herbert's satirical legal tales for television in Misleading Cases (1967). Co-starring Alastair Sim as the world-weary Stipendiary Magistrate Mr Justice Swallow, and Roy Dotrice as the court's self-confessed 'nuisance' and serial litigant Albert Haddock, and featuring a perfectly-picked supporting cast, this literate and mischievous series was, in a sense, a forerunner of Yes Minister (both of whose writers were great fans) in the way that it slyly demystified an aspect of the Establishment, and was praised widely for its ability to engage and entertain with 'humour which might otherwise be too academic for a lay audience'.

The full extent of Mills's impact and influence was recognised internally in July 1967 when he was promoted to the position of BBC TV's Head of Comedy. It was from this place of power that he would not only continue to produce programmes himself but also commission some of the most popular sitcoms, sketch shows and comedy plays of the second half of the Sixties, as well as find and foster a whole new generation of talented writers, performers and producer/directors.

'Michael was great', Bill Cotton (pictured) - who worked alongside him in the Light Entertainment Department as Head of Variety - would tell me. 'He was a proper gentleman. He could be a bit prickly at times, but he was worth it, Michael - whatever that advert says, "Because I'm worth it," he was worth it. And I was very fond of him. Very, very, well-read, a good judge of a script and a good judge of actors, too. He was a brilliant producer, with enormous taste and flair, and he knew how to put a show together, but he could also be quite impetuous and take some pretty big risks. If he had faith in something he would just push on with it regardless.'

One of those who would benefit hugely from his patronage was David Croft, who later told me what a unique kind of boss he was:

He was a marvellous and enthusiastic Head of Department. Everything was possible once you'd decided that you could do something. He didn't really discuss budgets. In a way he was flamboyant. I took over, for instance, a production of The Mikado from him [in 1967] and he'd already ordered elephants, lions, tigers. I spent the first few days cancelling things we couldn't afford, you know. But it was still a magnificent production which he'd initiated in the first place. It was called Titipu - I had a lovely cast and that sort of thing. So I mean he was wonderfully ambitious and he had a very broad picture of what we should be doing and what he could do. And he did it, you know. He was marvellous. Well, I suppose, in principal form, he was a bloody genius. And he could do everything in a television studio.

Having lived through the 'wild west' era of TV, Mills, as an executive, was often exasperated by the more methodical, bureaucratic and risk-aversive culture that he felt was fast-creeping in to constrict the younger generation of programme-makers (as well as encouraging some of them to simply go unthinkingly through the motions and dodge much of the decision-making), and so, in his determination to keep pushing people to be daring as well as disciplined, he could sometimes come across as abrasive and overbearing. The more indolent and unambitious of the staff might well have resented his manner, but, as a man who had been there and done it and got the long list of credits to prove it, one learned very quickly not to mess with Michael Mills.

As David Croft would recall:

He was fine if he thought you were good at your job. He'd be a friend and a powerful ally. But woe betide anyone he thought was lacking either in ability or application. If he wasn't very happy about the way, say, a cameraman was shooting stuff, he would go down there and take the camera from him and do the shot himself: 'From there, understand? That's what I want you to do - now go to it!' And, of course, the result was that the crew were inclined to hate him. But, he knew exactly what he was doing. No doubt about it.

It would be David Croft himself who experienced at first hand just how thorough, insightful and decisive Mills could be when, in 1967, he and his co-writer Jimmy Perry submitted their idea for a new sitcom, The Fighting Tigers, for his forensic appraisal and, they hoped, eventual approval.

First of all, Mills decided that the title wouldn't work, and, demonstrating his keen ear for conveying a theme, called it Dad's Army instead. He also ruled that Perry, who had his heart set on playing the role of the spiv Private Walker himself, would have to choose on which side of the camera he wanted most to be, because otherwise the presence of an actor who was also one of the writers might cause resentment among the rest of the cast.

He was just as closely involved, and opinionated, when it came to picking the right actors to play each part, with the role of Sergeant Wilson seeing the swiftest of his several interventions: 'You must have John Le Mesurier!' he barked at Croft and Perry. 'He suffers so well!' Mills was also smart enough, after being initially resistant to the idea of Arthur Lowe playing Captain Mainwaring (on the grounds that he was considered in those days 'an ITV actor'), to listen and let his colleagues convince him to change his mind about that particular piece of casting.

Among his other decisions on details was a revision to the title of the town: although he liked the south-east coastal setting, he disliked the original choice of 'Brightsea-on-Sea' for its name, so he pressured David Croft until the latter came up with 'Walmington-on-Sea' as an alternative. Some of the characters' names, too, Mills argued, did not sound quite right: 'Mainwaring' suited the pompous captain, as did 'Godfrey' the old man and 'Pike' the young boy, but he did not care at all for the dour Scot being called 'Private Jim Duck' - he suggested it be replaced with 'Frazer' - or the spiv as 'Joe Fish' - he proposed 'Joe Walker' - or the butcher 'Jim Jones' - he preferred 'Jack Jones'.

Mills also felt that the platoon would benefit from being made somewhat more variegated in terms of background: one character, for example, might be made an ex-colonel or perhaps a retired admiral, another the ex-officer's old gardener, and maybe young Pike would be more interesting if he became the local young misfit, and, while one was at it, a little more regional diversity would not go amiss, with Frazer's Celtic crankiness being given a stronger expression.

The resultant 'Mills-ified' version of Dad's Army would be a testament to the way his unrivalled toolbox of talents enhanced so many of the BBC's comedy successes of the time. 'You never resented his involvement,' David Croft would tell me:

Because it was obvious that he knew what he was doing, and he was helping you with his experience and expertise. He'd blow through a show like a tornado sometimes, because he'd be able to look at every aspect and quickly spot what might need to be altered or improved, and he genuinely wanted to help you to make the best of what you were doing. You were a programme-maker getting this invaluable support from a boss who also happened to be a very experienced top-class programme-maker himself. He was so different from the typical kind of executive who would succeed him. With Michael, he'd trust you when you had an idea, and would rub his hands together, roll up his sleeves and say, 'Let's get to work!' That's how and why so many great shows got made.

Another example of how inspired Mills could be was the way that he came up with a new starring vehicle for Frankie Howerd. During a short visit to Sorrento with his colleague, the then-Head of Light Entertainment Tom Sloan, early in 1969, the two men went off on a tour of the ruins at Pompeii. Deviating from the main crowd, as usual, Mills wandered off to explore some of the places where the old shops and bordellos had been. 'It's amazing,' he suddenly exclaimed to Sloan. 'I expect Frankie Howerd to come loping round the corner!'

Mills had seen Howerd a couple of years before in the stage musical A Funny Thing Happened On The Way To The Forum, which had been inspired by the satirical farces of the ancient Roman playwright Plautus, so the vision of the comedian back in a toga made sense. 'Why not?' said Sloan of the suggestion, and the seed was sown.

Once Mills was back in London in his office at Television Centre, he plucked a copy of the works of Plautus from a drama colleague's shelf and started scouring it for sitcom storylines. He then had his scribbled notes typed up and sent on to the Carry On scriptwriter Talbot Rothwell, along with a card saying, 'What about this for Frankie Howerd?' Rothwell loved the idea, wrote a sample script, Mills sent it to Howerd, who was delighted, and, within a few months, the first episode of Up Pompeii!, with Mills as producer, was out on the screen.

It was around this same time that Mills, acting on the advice of Barry Took, also commissioned Monty Python's Flying Circus, and in this case, after finding the first samples of material interesting but somewhat alien (and rather unnerved by the sight of a sozzled Graham Chapman crawling on the floor at a Christmas party trying to bite sundry people's ankles), he sensed that the best way to support this particular show was, as he would put it, to 'leave it to breathe'. Believing in the boundary-pushing band of writer-performers that had been assembled - 'You buy people,' he liked to say. 'You buy their brains and intelligence' - he issued some basic advice and then left them to it: 'Don't get too clever. If you try to do too much you won't get away with it and you'll bugger your show up. Now start quietly.'

The Pythons, judging by their later reminiscences, probably assumed - because their direct contact with Mills tended to be limited to the odd tetchy dressing-down following some or other controversy - that he only reluctantly tolerated their show's continuing presence in the schedules, but the reality was that, discreetly behind the scenes, Mills was regularly defending and protecting them. His apparent aloofness was merely the best way, he felt, to feed their sense of freedom.

There would, inevitably, be the odd instance when Mills, with his passion for people and programmes, was guilty of loving not wisely but too well. The most painful example of this was the way in 1971 that his complete belief in the comic talent of Peter Cook saw him doggedly defend the latter's ill-starred venture into the talk show genre with Where Do I Sit?. 'That was really hard,' Bill Cotton (who by that time was Mills's boss) would tell me, 'because Michael had to keep pleading with me to keep it on air, and I hated having to clash with him, but in the end I just had to say, "You won't get it right, Michael. Peter just can't do it". Michael was the last person I wanted to do that to, but not even he was right all of the time.'

Most of the time, however, Mills was remarkably astute in what risks he chose to run. He was just tiring a little of having to go into battle each time, on other people's behalf, against a BBC bureaucracy that seemed to be growing more infuriatingly byzantine with each passing year.

Always too attached to the hustle and bustle of the factory floor to find the lofty executive life entirely tolerable, Mills relinquished the post of Head of Comedy in 1971 in order to return to producing full-time. Now free of the regular burden of having to plough through piles of paperwork, he proceeded to make more impressive shows and series, including in 1972 Clochemerle (Galton & Simpson's critically acclaimed, and beautifully filmed, nine-part adaptation of Gabriel Chevallier's comic novel) and Scoop (Barry Took's audacious reimagining of the Evelyn Waugh novel with Harry Worth as William Boot); in 1973 a memorably unruly Spike Milligan special, even by his standards, called Milligan In Summer; and in 1976 another set of widely celebrated Wodehouse plays.

One further demonstration of his rare sense for sniffing out the projects that he could make soar came with his championing of Some Mothers Do 'Ave 'Em in 1973. As Bill Cotton recalled to me, while others were left unimpressed by the proposal, Mills saw something in it right from the start:

He was directly responsible for the casting and production of Some Mothers Do 'Ave 'Em. And it was written by a chap [Raymond Allen] who sent in the minimum of ideas, but it just struck a chord with Michael and he put his faith in it. He'd been to see No Sex Please, We're British and he'd seen Michael Crawford and he said, 'He is the very one'. I remember him saying it to me with absolute conviction: 'He is the very, very man who can do this!' And so he went and got him, and they used to all write it as a kind of co-operative, as far as I could make out. He was heavily involved in every aspect, even down to asking for that Morse code theme tune. And it became another hit.

In January 1974, Mills married Valerie Leon, the famously voluptuous actor ubiquitous at the time for her leather-clad ads for Hai Karate aftershave, whom he had met on the set of Up Pompeii!. They would have two children together (Leon and Merope), one of whom, like his own father, would go on to grace the pages of The Guardian.

Another change in his life came in 1975, when Mills left the BBC for the third and final time. Although he would still go on to make, as a freelance, one final series of Wodehouse Playhouse for his old employer, he moved over to Thames TV, where he would be afforded a considerable degree of freedom to select and shape his future projects.

Starting with the Esmonde and Larbey sitcom Get Some In! (1975-8) and the sketch-based The Howerd Confessions (1976), Mills continued to prove himself one of the most shrewd and stylish crafters of comedy programmes. His sitcom based on the writings of H. F. Ellis, A. J. Wentworth, B.A. (1982) - which had been a project he had been wanting to make for a fair few number of years - was a particularly fine example of his art, even though its reception was muted by the sad death, before transmission, of its star, Arthur Lowe.

He remained as enthusiastic as ever, if a little more eccentric, during his final years at Thames. Brenda Blethyn, whom he chose to star alongside Simon Callow in the delightful 1984 sitcom Chance In A Million, would recall (in her memoir Mixed Fancies) Mills appearing to revert even more strongly to his Navy roots during rehearsals, summoning people by shouting out 'Ahoy,' wearing a duffel coat and looking 'as though he was conducting operations from the bridge of a ship'.

He was also, by this time, less inclined to excuse the indiscipline of youth, and, as a consequence, rather more prone to bouts of bad temper. A twenty-six-year-old Stephen Fry bore the brunt of one of these eruptions when, after being booked for a one-off role in an episode of Chance In A Million, he miscalculated how long it would take him to travel from his home in Islington to the Thames studios at Teddington Lock and ended up arriving more than half an hour late. An agitated Mills, his spectacles swinging like a scythe on the string around his neck, not only administered an unnervingly stern lecture to the inexperienced actor but also announced that he would be writing a letter to his agent complaining about his unprofessional attitude. His aim, nonetheless, always remained a positive one: he just wanted the right lessons to be learnt.

Michael Mills died, aged sixty-eight, on 7th January 1988. His many achievements had been recognised during his lifetime by a number of awards, including two in 1965 from the Guild of Television Producers and Directors for 'Best Light Entertainment Producer' and 'Best Script', and one for 'Best Dramatisation' in 1967 from the Writers' Guild of Great Britain for his (and Richard Waring's) adaptation of the work of P.G. Wodehouse. His legacy, however, aside from a great and remarkable body of work, would be the innovations that he established, the high standards that he set and the creative courage that he inspired.

It is said, by those with the self-awareness and humility to acknowledge it, that what advancements they may make are only achieved by them standing on the shoulders of giants. One of those giants, as far as British broadcasting is concerned, will always be Michael Mills. We would do well never to forget him.