Hearing Sir Ian McKellen gleefully call Sir Derek Jacobi "a cheating slut" is a joke we're not going to get tired of for ages.

And that's one of the less vicious insults being hurled about in episode two of our favourite new sitcom.

After their hilarious vampire-like horror last week at the curtains being opened, Freddie and Stuart actually venture out into daylight this week.

New neighbour Ash asks them for their advice about women, actor Freddie is excited about the Doctor Who fan club screening that he's about to attend (having been voted 10th favourite villain of all time) and Stuart is suspected of having an affair.

But truthfully, the plot scarcely matters when the dialogue is so delicious, the relationships so sharply drawn and the acting so sublime.

Frances de la Tour ("you remember our friend Violet") continues to drop by unannounced to purr throatily over Ash, but it's their other dotty friend Penelope (Marcia Warren) who delivers one of the lines of the night. Actually, make that the whole year.

Tonight, Freddie and Stuart emerge from their fusty flat to visit - for them - an alarmingly bright clothing store to buy a smart overcoat. Freddie, an actor whose ego is far more swollen than his CV, needs to look his finest for a Doctor Who screening - "I have been voted the tenth most popular villain of all time!" he coos, making the most of this dubious accolade.

What gives this a curious subtext is that Ian McKellen actually did voice a baddie in Doctor Who last Christmas, while Derek Jacobi played number-one villain, the Master, quite thrillingly in 2007 and has attended several conventions himself.

A torrent of tart asides, camp banter and even dog prodding flows in this terrific new comedy. Frances de la Tour is magnificent as Stuart and Freddie's man-eating pal, Violet, whose "rather broad tastes" will extend even to Who fans. Meanwhile, she's panting after their neighbour Ash, takes him shopping too and tries to get him into a pair of Speedos - all of which allows Ash (former Misfits star Iwan Rheon) to appear less gormless than last week.

The domestic squabbling of two elderly gay men does still feel like an admirably subversive concept for an ITV primetime sitcom. But everything else about this series is traditional and generic to the point of tedium. Maybe the idea was to impose broad humour on to what some still consider to be a niche lifestyle. But most of Vicious is not so much broad as played-out and redundant. The canned laughter; the telegraphed sight gags; the rigidly choreographed scenarios. The performers (particularly the magnificent Frances de la Tour) are the best things about Vicious but, all in all, it feels like a well-intentioned throwback.

For just when you thought TV couldn't get any more 1973 following from the BBC's The Wright Way, along comes ­Vicious, a comedy with Sir Ian McKellen in a silk dressing-gown standing regally - nay, queenly - on a staircase and squawking camply at Sir Derek Jacobi in a fetching sleeveless pullover who's squawking camply back at him.

The trouble with The Wright Way is that it doesn't seem as if Elton is being nostalgic for how sitcoms used to be, or that he's operating in defiance of shows like The Office and all those pale imitations, churned out of David Brent's hyper­active photocopier. The Wright Way appears to be the funniest and most relevant programme he could make, which isn't very funny or relevant at all.

Vicious, though, is a more self-conscious attempt to evoke the spirit of '73. It's completely stage-bound. We never leave Freddie and Stuart's flat. The doorbell rings often; phone, too. Sometimes Stuart (Jacobi) shrieks: "These aren't calling hours!" Most likely, there have been very few callers in the 40-odd years the pair have lived together, blissfully ignorant of the changing world (acceptance of homosexuality, not all comedy looking like Brian Rix is about to enter, stage left, mightily flustered). A modern sitcom like Modern Family has its gay couple flamboyantly "out" and adopting babies; Stuart hasn't even told his mother about Freddie.

Why's it called Vicious? Well, these guys are very bitchy. "Are you wearing mascara?... Your mother looked well for someone who doesn't have a heartbeat... I'm surprised you can see it through the milky film that coats your cataracts."

At first I quite enjoyed the campery. Frances de la Tour popped in, reminding us of her big 1970s flat-based hit (what was it called again, Rising Camp?). But, in every sense, where can this one possibly go from here?

Radio Times review

Vicious (ITV Player) put Derek Jacobi and Ian McKellen on a standard stage/sitcom lounge set - front door on the left, swing door to the kitchen on the right, stairs in the background - and let them howl and scratch for half an hour as Freddie and Stuart, who had been lovers for more than 50 years and had now settled into their bitter, argumentative dotage on the sofa.

The challenge was to enjoy the proceedings as much as the two stars, as McKellen ripped through scores of searingly bitchy lines, peaking with a cracker about Stuart "pouring your blandness over every surface", while Jacobi freed his right arm to become one of the campest limbs ever seen on TV.

Many viewers really, really didn't enjoy Vicious, throwing all sorts of criticisms that largely bounced off. It was stagey, retro and gaudy, they said, pointing out all the things it was actively trying to be. It entrenched gay stereotypes, they said, looking to a riotous sitcom for assiduous social realism. It used canned laughter, they said, referring to the live studio audience.

The complaint that had merit was that jokes mentioning rape are basically never funny, even if Frances de la Tour as fag-hag Violet fretting about virile young neighbour Ash (Iwan Rheon) was cartoonish and abstract enough to be as near to harmless as they come, as well as being sinfully well timed. (McKellen: "For God's sake Violet, nobody wants to rape you!" De la Tour: "What an awful thing to say.")

The line still should have been taken out, and was evidence that Vicious might not have a heart, which means it'll drag as soon as the one-liners falter. But while it's steaming, Vicious is hot.

Vicious, my type of television, is the panto-style tale of two heavily theatrical, caustic old homosexuals - Ian McKellen and Derek Jacobi - living in a dark flat, curtains drawn, loathing everyone, with occasional visits from sublime proto-hag Violet - Frances de la Tour - who turns up to add deadpan fuel to their bitching bonfire. Broad, brash and shallow this may be, but if this isn't at least a rough outline of my life in the Starlight Home for Retired Hacks circa 2057, then something has gone very awry. I rather loved British stalwart Marcia Warren as Penelope, when the ensemble sat sipping tea at a gay wake, remembering their dead friend's terrific affection for handsome men. "Wasn't there a wife?" Penelope said, scrunching her face to remember the finer details of the 1960s, "I'm sure I remember a wife?" "Ugh, 17 years," McKellen hissed with an airy wave.

Most of the opening jaunt of Vicious featured the aged couple making colossal fools of themselves by flirting with their new twenty-something neighbour. If one really wants something to get terrifically het up about, one could say the whole show glorified sexual assault and augmented gay stereotypes. I just took it for a lovely, daft, gay, romp full of acidic quips. It's too beautifully easy and temporarily satisfying to detest all new comedy on sight. I do it myself.

The opening titles roll, the first scene appears establishing characters in broad strokes. "Ugh, I hate everyone here!" the internet roars, 'I hate the fact this was even made, I hate everyone involved, in fact this shit-fest is the amalgamation of all that is wrong, safe, depressing and nepotism-fuelled about British TV commissioning." Obviously, in the case of BBC1's The Wright Way, this is not only true but an understatement, but, in most cases, it's just a show gathering momentum.

Vicious stars Ian McKellen and Derek Jacobi as a pair of gay old queens sharing their lives and a crepuscular flat that looks like a relic from a 1970s sitcom set.

That design may well be a consciously ironic reference but it didn't make the setting any more appealing. There was something dankly theatrical about it. In theory, that befits McKellen's role as an ageing rep actor who, in the show's best line, "once killed a prostitute in Coronation Street".

But there was also something dankly theatrical about the whole concept - the over-pronounced acting, the laboured dialogue, the arch gestures, McKellen's dressing gown - that felt like being trapped in a dramatic workshop on camp with two self-regarding thespians, but not nearly as amusing as that sounds.

Of course, the radical new aspect of the show is that it's a sitcom about gay men on mainstream television. While that's a development worthy of applause, it doesn't, unfortunately, command laughter. Nor did Frances de la Tour, reprising her Rising Damp role 40 years on, but this time more as a female Rigbsy than an older Miss Jones.

She found herself in the unenviable position of having to try to out-camp Jacobi and McKellen, which is rather like having to out-butch Schwarzenegger and Stallone. Everything was at a hysterical pitch, but nothing happened. Instead, the dreadfully static nature of it made you long for the energy and pace of the commercial break.

This first episode deals with the passing of one of the couple's friends who was supposedly infatuated with Freddie. But later it transpires that he was actually in love with Stuart and this sets off a blazing row between the pair. Eventually the duo are reconciled but I get the impression that this is the formula that the series will take every week. The problem with Vicious is that it is incredibly old-fashioned and mainly survives due to the chemistry between its two leads. While McKellen and Jacobi appear to be having a ball, the scripts are very weak and there is only so many times you can hear the pair insult each other.

The supporting roles are woefully underwritten with Frances De La Tour given very little in her role as the waspish Violet. Meanwhile Iwan Rheon, who was so great in Misfits, looks embarrassed most of the time and his character Ash is basically presented as a piece of meat for the older characters to salivate over.

It doesn't surprise me that Vicious lost a million viewers during its half hour slot as I think people would've grown tired of the programme by the end. While some people seemed to enjoy it, I personally felt that this was very old-fashioned and not particularly funny.

Rape offers such a rich vein of comic potential that I am bewildered as to why the world of sitcom has overlooked the subject for so long. But not to worry, because Vicious remedies the situation within its first ten minutes with not one, not two, but three rape gags in succession, culminating in the following chucklesome exchange:

Man: Nobody wants to rape you.
Woman: Don't be so cruel.

Mercifully, they didn't move on to discuss child rape, or I swear my sides would have just burst. Presumably the writers are saving this for a later episode - not wishing to use all their best material first time out.

Vicious stars Ian McKellen, Derek Jacobi and Frances de la Tour, and I can only surmise that all three have close relatives being held hostage by the production company because I cannot think of any other reason why such luminaries of stage and screen should agree to such dross.

The same applies to highly respected playwright Mark Ravenhill and former Will & Grace writer Gary Janetti, who provided the scripts, presumably encouraged by the regular arrival of loved ones' body parts in the post.

Jacobi and McKellen play an elderly gay couple - one is camp, and the other less so. And that is about as far as the characterisation goes. Their relationship is based upon bickering and making acerbic comments, because that's what gay people do. In episode one, the couple are thrown into a complete tizz because a handsome young man has moved into their block of flats.

The show is so busy trying to be outrageous that it fails to exercise any quality control on the jokes it lets through. "I went to Oxford!" protests Jacobi, when his intellectual credentials are questioned. "For lunch!" replies McKellen. With conviction, it has to be said, because he is a fine actor. But who knows what agonies he must have suffered delivering such a limp line?

The most annoying thing about Vicious - as opposed to being just plain unpleasant, lazy or depressing - is that somewhere in its stagey, studio-bound set-up, populated by stereotypes, is a decent sitcom struggling to get out. Let me know if it happens.

What a line-up for a sitcom; three of our most accomplished actors - Ian McKellen, Derek Jacobi and Frances de la Tour - star, and the writers are the super-talented playwright Mark Ravenhill and Gary Janetti, who used to work on Will & Grace, one of the classiest comedies on American television in decades. And what do you get? Well, not quite the laugh fest that it might have been (or may yet become), but an opener that had a reasonable hit rate.

Vicious is another back-to-the-future comedy, a one-room sitcom with two of the queeniest gay men to grace our screens since the dear departed Larry Grayson and John Inman. If Dick Emery's Clarence had made an appearance he wouldn't have looked out of place and, with De la Tour's presence, it could be called Rising Camp (sadly not my line - I nicked it).

Freddie (McKellen) and Stuart (Jacobi) are a bickering, gossipy gay couple who live in crepuscular gloom in their Covent Garden flat. Freddie is a never-has-been actor ("You may have seen me in a scene in Doctor Who") who has long since lost his Wigan accent; Stuart is a one-time barman who is still not out to his mother. He's waiting for the right time - "It's been 48 years!" cries Freddie.

Into the flat upstairs moves the attractive youngster Ash (Iwan Rheon), who attracts appreciative looks both from the men and their faghag friend Violet (De la Tour); most of last night's episode concerned their convoluted attempts to find out if he was gay or straight. Don't people just ask if they're interested to know?

The cast are clearly having fun with the bitchy lines, but Jacobi is overdoing the flounce and Ash is as yet underwritten. Too much of Vicious relies on tired comedy tropes; older people are gagging to have sex with people young enough to be their grandchildren, they don't know anything about youth culture ("Is Zac Efron a person or a place?" Violet asks); or they're deaf, dotty and fall asleep easily. Oh please. As for the double rape "joke" everyone involved should be ashamed of themselves, including director Ed Bye.

On the evidence of last night's first episode Ravenhill and Janetti can't decide if Vicious is lazy retro fun for all the family, or an edgy post-watershed show that's taking us to places never previously negotiated on British TV. Let's hope it's the latter over its seven-week run.