It's strange how little the art of the impressionist has evolved since the heyday of Mike Yarwood. But this new sitcom written by Matt Morgan achieves the unusual feat of placing this variety club act in a fresh context. Terry Mynott is Martin Hurdle, a quiet, unremarkable middle-aged man with a hidden talent.

Hurdle's a freakishly good impressionist, prone to slipping into Terry Wogan in traffic jams or getting his own back on his boss over the intercom at work. So far, so ho-hum. But where "The Mimic" feels both promising and unusual is that Martin's mimicry is, at this point, a dead end. Martin has a rubbish job. He has a charming but, as far as we can tell, unfulfilled relationship with [p[Jo Hartley]'s Jean. And he has an 18-year-old son whom he's taking the first tentative steps towards getting to know. In other words, The Mimic is brave enough to be gently melancholy rather than uproarious - Martin's gift feels more like a product of confused identity and low self-esteem than any desire to entertain.

It will be interesting to see whether this ventures into more conventional sitcom realms as it progresses - on the evidence of this opener, it could be a subtle, understated treat.

If, like us, you're of the opinion that impression shows got a bit stale the thousandth time Jon Culshaw declared "My fellow Americans" on Dead Ringers, then you might appreciate the new take on the comedy sub-genre offered up by The Mimic.

Terry Mynott is the star of this not-entirely uplifting sitcom, playing an unremarkable maintenance man with a hidden talent for celebrity impressions. From Terry Wogan to Morgan Freeman, he can be pretend to be pretty much anyone - but he's soon brought back to reality when he discovers that he may be the father of his ex's 18-year-old son.

Sponsored innuendo, anyone? Graham Norton hosts seven hours of celebrity chat to raise money for Comic Relief. He's gunning for the Guinness world record for most questions asked on a TV chatshow, and Keith Lemon, Sarah Millican and Russell Tovey are among the stars queuing up to answer them. Terry Wogan and Nick Grimshaw are ready to take the hot seat once Norton runs out of chat (unlikely) and to give viewers a break from his lovable face. With music from Example, Hurts and Laura Mvula.

If his chat show is anything to go by, Graham Norton could keep up his chirpy line in celeb quizzing in his sleep. Which is just as well, for tonight he embarks on a mammoth six-hour chat-athon in a Guinness Book of World Records bid to pose the most questions asked on a TV chat show. All in aid of Comic Relief. Our Graham's not flying solo, though - Frank Skinner and Terry Wogan are on the subs bench and there's music from Example, Paloma Faith, Hurts and Laura Mvula. Celeb guests chatting along include Louis Smith, Martin Freeman, Russell Tovey, Heston Blumenthal and Sarah Millican.

Norton foregoes the usual physical challenges beloved of Comic Relief for a more sedentary affair: attempting to set the Guinness world record for most questions asked on a TV chat show, which should see him broadcasting into the wee hours of Friday morning. We can only hope that Graham also dispenses with his usual tipple of wine with guests, otherwise this chatathon is going to get very messy.

So far guests announced as appearing on the sofa include Ronnie Corbett, RT's Sarah Millican, Martin Freeman, Elle Macpherson, James Nesbitt, Louis Smith, Heston Blumenthal, Warwick Davis, Russell Tovey and Jimmy Carr, though you wouldn't bet against an American superstar or two turning up, too. Music acts will include Example, Paloma Faith, Hurts and Laura Mvula.

Graham will be assisted by co-hosts Terry Wogan, Frank Skinner and Nick Grimshaw, and viewers can help, too, by submitting questions via Twitter and Facebook. And by donating money.

Stephen Fry's Bafta performance fails to impress

Stephen Fry, who hosted the Bafta awards, is criticised by broadcasting veterans including Sir Terry Wogan and Maureen Lipman.

This is a show about gripes, so let me air mine. Room 101 is pleasant enough viewing but it never quite takes off. There are amusing bits, as Victoria Coren launches into a tirade about fancy tea or Terry Wogan rails against excess packaging ("Has anyone tried to break into a toothbrush lately?") but pretty much every episode has had a slightly desultory feel to it, with none of the comic sparks that fly in, for instance, Would I Lie to You?

Also, watching celebrities - even witty ones - grumbling about mildly annoying aspects of life (tipping in restaurants and windows that don't open are two tonight) doesn't put you in the Friday-night mood, does it? There, gripe over.

Those familiar with the work of living vaudeville legend Count Arthur Strong (Steve Delaney) will need no introduction to his work. Old-school entertainer, after-dinner speaker, raconteur, ventriloquist, mind-reader and celebrity chef do not do his illustrious career justice. For those unaware of his work, he is also the master of malapropisms. Never has the English language taken so much of a lashing as when the Count gets his gums around it.

Here he finds himself railing against the hopelessness of public transport and decides his only option is to get his minx out. That's a Hillman Minx, which he's not driven for 30 years. A chain of events is set in motion by this dangerous decision that sees my hero sending an innocent insurance clerk into an abyss of despair: "Is there something wrong with you?" asks the Count as he tries to get a quotation. "Have you been off work and come back too soon?"

This altercation ends with a pricey quote because Count Arthur Strong works in the entertainment industry and "might have someone like Terry Wogan" in the back of his car.

Why should he pay for Terry Wogan to travel in his Minx? Does the clerk think he should take him shopping and pay for his food bills as well? There's only one thing for it: the Count must confront Terry Wogan himself...

I shall leave the marvellous malapropisms to him. Just be sure not to mess thus.

Lee Mack and David Mitchell's quick-witted cross examinations are by far the best bits of this show, and tonight they get to bounce off Terry Wogan, who claims, among other things, that he likes to fire a loaded pistol every Christmas. The broadcasting legend also gives Rob Brydon an excuse to roll out his impression.

Terry Wogan is on the panel this evening, so you know it's only a matter of time before host Rob Brydon employs his scarily accurate impersonation of the great broadcaster. But he's not the only one present with a facility for accents, as comedian Kevin Bridges proves when he drops his Scottish brogue quicker than you can say "John Barrowman".

As ever, though, it's the forensic cross-examinations that make the show, particularly those directed at Sir Terry, who has to convince the opposing team that he performs minor acts of arson for kicks and begins his Christmas Day celebrations in a most unorthodox manner. You'll also get a strange buzz when he says the words "blank" and "blanks" again after so many years.