TV review: Vicious (ITV) starring Sirs Ian McKellen and Derek Jacobi - The only laughter it provokes is canned

For the next six weeks, Monday evening on ITV is a study in comic contrasts, almost scientific in its clarity. At 9pm you can watch Vicious, a sitcom filmed in front of a studio audience in classic three-camera style. And then at 9.30 you get The Job Lot, a single-camera comedy set in a Midlands job centre. One is a star vehicle, featuring Ian McKellen and Derek Jacobi as an elderly gay couple, and offering regular slots to Frances de la Tour and Marcia Warren as female friends. The other is an ensemble piece, with several recognisable faces but no standout star. One of them is accompanied throughout by the raucous laughter of people so gripped by hilarity that they sound as if they're on the brink of being hospitalised. The other is actually funny.

I don't know who it is who makes up the studio audiences for sitcoms or what they're injected with before the recording begins, but, as Ben Elton's The Wright Way demonstrated last week, there is virtually nothing that they won't laugh at. Like laboratory animals trained to respond to some arbitrary stimulus, they react to anything that is even vaguely punch-line shaped. This turns out to be quite handy in Vicious, which is full of lines that have the cadence of comedy but often prove to be devoid of wit when examined more closely.

Or to employ a wit so dubious that an appalled silence might be a more reasonable response. An example: "You let a complete stranger use your loo?" says Frances de la Tour's character when she discovers that Freddie and Stuart's lavatory is occupied. "What if he comes out and rapes me?" Gales... no... tornadoes of laughter.

The basic schtick in Vicious is high-camp bitchiness, a form that reached an apogee in the American sitcom Will & Grace (on which Gary Janetti also worked). This is a sadly depleted version, though, and it's delivered by McKellen and Jacobi as if they're playing in Wembley Stadium and only the upper tiers are occupied, with a heavily semaphored effeminacy that seems to belong to an entirely different era.

That is partly the point, of course – they're supposed to be social fossils – but unfortunately nothing else in Vicious provides a believable backdrop for their self-dramatisations, from the inexplicable eagerness of the young straight neighbour to insert himself into their lives, to the jerky clockwork of the plot. Only Marcia Warren comes out of it with her dignity intact, as an absent-minded friend. Seems almost blasphemous to say it but McKellen and Jacobi should watch her and take some notes on comic acting.

Nobody laughs for you in The Job Lot, which is full of those poised silences that are a feature of modern sitcom style, as non sequiturs falter to a stop or a character is left to silently absorb the absurdity of someone else's behaviour. But there is plenty for you to laugh at yourself. Sarah Hadland plays Trish, the job centre manager, in a way that makes you completely forget her more cartoonish performance as Stevie in Miranda, and Russell Tovey appears as Karl, a disenchanted employee who walks out after dealing with a particularly reluctant job seeker, and then walks straight back in again when he catches sight of the beautiful new temp.

There's a nice turn by Jo Enright too as Angela, a surly bureaucratic jobsworth. Most importantly, the comedy lies not in the lines as such but somewhere between what's said and how it's said. "I'd go mad if he wasn't here... I really would," says Trish brightly, commending Karl to the new girl. "I'd self-harm." And then, instead of the grating coercion of mass guffawing you get an awkward silence, as Trish realises she's said too much and the other characters try to think how to fill the gap. In my case, it was filled with a laugh.