We've seen Greg Davies play a teacher before, of course, and the workless, foul-mouthed truce struck between him and his flock here does smack a little of Jack Whitehall's Bad Education, but Man Down's shortcomings in originality are nulled by a relentless volley of gags, all at Davies's expense, and with many arriving courtesy of a brilliantly cast Rik Mayall as his sadistic prankster dad. Crude, silly and very funny.

Penultimate episode of Greg Davies's by-the-numbers debut comedy, in which he plays newly single, perennially chaotic drama teacher Dan. This week, he gets help from strait-laced buddy Brian while preparing for an unexpected date, and his dad offers him a scary insight into his own former love life. Despite a brilliant turn from Rik Mayall as Dan's father, the series has relied thus far on cheap, un-PC gags and surreal moments that don't quite reach the pandemonium of Davies's last project, Cuckoo.

Clueless Jo and Pringle tube-man lookalike Brian leave Dan kicking his clumpy heels for a weekend. He's so mind-numbingly bored he finds himself angling for an invite to his niece's birthday party, to which ex-girlfriend Naomi just happens to be invited. Obstacles in the form of a colossally impractical cake, an ultra-defensive community support officer and a Renault Scenic stand between him and the promise of free jelly. A gradually improving sitcom, with Rik Mayall stealing the show yet again as Dan's malevolent dad.

Dan is still vainly trying to save his relationship with Naomi. He's engaging the services of "Mad Nobby" to fix his car seat and has planned a get-back-together meal of fried mince, as well as a dedicated programme of nostalgia where he lists their past good times. It goes as well as you can imagine, particularly as he manages to end up in a skin-tight salsa dancing outfit beforehand. Lovely to see Rik Mayall's mischievous face back on telly; as Dan's dad he tips his single scene into excellence with little more than his eyebrows.

Teacher man Dan (Greg Davies) may be down on the romantic front but he's not yet out for the count.

As the sitcom pratfalls continue, Dan fixates on winning back his ex - by collecting proof that she was wrong to dump him.

Meanwhile, the world around him continues to make as little sense as he does: an invitation from his dad (Rik Mayall) to play a game of swingball blasts open a whole new ball of confusion.

Strictly fans will find an extra treat tonight as Dan and his friend Jo perform a salsa to entertain some hospital patients.

It's all part of Dan's desperate scheme to try and convince his former girlfriend Naomi that he's a fun person with a fully rounded social life. Not much chance of that, as tonight he is also relying on the seductive power of mince to win her round. And what woman can resist mince?

Thanks to Greg Davies' towering energetic idiocy, Man Down offers reliable silliness - and it's the ideal vehicle for Davies to exploit his background in both teaching and stand-up. But he doesn't save all the best gags for himself and the support from Roisin Conaty and Mike Wozniak as his best mates Jo and Brian are outstanding.

The casting of Rik Mayall as Dan's father is inspired, and the kids who have the misfortune to be Dan's drama students are game, recognising he is a bigger kid than any of them.

Dan (Greg Davies) is still in deep denial about Naomi's departure. But what isn't clear at this stage of this wilfully quirky sitcom is why she was with him in the first place. Dan is a boisterous, selfish, puerile child in a large man's body. Despite earning his living as a teacher, he addresses bespectacled pupils as 'four eyes'. He performs tricks with his cock to impress women. In fact, the only aspect of Dan to attract sympathy is his even more loathsome father (a gleefully well-cast Rik Mayall).

Man Down is clearly meant as a real life cartoon of sorts. The scenarios are ridiculous, the humour basic and broad and the performances exaggerated. But to stick with the show, we'll need someone to root for. And Dan just doesn't feel like that man until the final frame of tonight's episode where he realises that a plate of over-cooked mince isn't going to woo his sweetheart back. Despair for Dan, but a glimmer of hope for the series perhaps? Either way, Man Down needs a little more of this to avoid one-trick-pony ignominy.

Greg Davies brings his gift for the deranged to a new sitcom that is so loaded with childish eccentricity it practically bludgeons us into laughter. Davies is the six-foot-eight comedian who made a name for himself as a comic actor in The Inbetweeners and Cuckoo. There he played exasperated adults; here he plays maddening man-child Dan, a hopeless oaf who in the opening scene fantasises about designing a fart-powered hovercraft while his girlfriend points out he still hasn't replaced their broken light bulb.

When she finally decides to leave him, Dan is driven to new lows, not helped by losing his trousers and being attacked by his dad (Rik Mayall) in a bear outfit. None of this is subtly nuanced or anything, but there are real, stupid laughs, not least at the sight of Dan driving round in an old banger with his seat so far back he has his arm out of the rear window.

Greg Davies's latest venture into sitcomland is comedy writ large, from the initial fart joke, to a pair of lost trousers and some slapstick scenes that are so preposterous as to be surreal.

The premise is a tried and tested traditional one - newly dumped, middle-aged teacher (Davies) lives in a flat attached to the house of his mum and dad (Rik Mayall, in a near-perfect piece of casting, if you overlook the fact that Davies and Mayall are roughly the same age), and is surrounded by idiosyncratic/idiotic 'fucking mental' friends who do things such as sing him out of bouts of angst under the disapproving gaze of a battleaxe café proprietor.

It's touches such as these - and Davies's utterly silly but joyous classroom scenes, and lines such as 'He's a good boy. He's normal. He's not into your rubber shorts, your plastic fists, your glory holes,' delivered by the local tailor discussing his work experience schoolboy - that could have you warming to both Davies and the series, particularly if you like puerile, juvenile, violent comedy. Ageing The Young Ones fans will love it.

If you were a fan of Greg Davies as the terrifying Mr Gilbert in The Inbetweeners, you'll love this new sitcom he's written... his dad (a brilliant Rik Mayall) bullies him, his girlfriend is sick of him and his friends are crazy. It's a promising debut.