TV review: Run - Abandon all hope – here comes Olivia Colman

Good grief, it's Olivia Colman – drop everything and run, you fools! Wonderful actress she may be, but as a harbinger of doom, Colman is right up there with two-headed frogs and yolkless scotch eggs. Her appearance in a serious drama usually means death, mayhem and much rending of garments. So it proved in Run, the quartet of linked dramas on Channel 4 last week. Colman, mistress of despair, was only in the first one, playing Carol, downtrodden single mum to two louts. But she made her hour count, misery swirling around her like a turd in a blender. Her boys beat a stranger to death, her ex takes decisive action by punching her in the stomach, and she drinks herself to sleep every night after a bit of quality swearing.

The misery spread. Successive episodes took their cues from Monday night's opener: the stranger who Carol's boys killed was a Pole involved in arranging illegal marriages, whose wife is left broke; Carol sold stolen mobile phones on to a young Chinese illegal immigrant who is forced to do anything to pay off her debt to the gangster who smuggled her into the country, from enduring rape to selling pirate DVDs; one of her DVD customers is a recovering junkie who is desperate to maintain contact with his estranged daughter.

As sociology, I imagine that it was impeccable on the utter shittiness of life on the margins and the fact that in those shadows women are forever trapped by the god-awful agendas of men. I learned something, too: to my shame, I hadn't given much thought to the DVD sellers who drift in and out of pubs and shops, and the bloody economics that often drive them there.

But, like the opening credits footage, an anonymous tract of urban hinterland shot from a moving train, the tales in Run mostly just rolled past, a diorama of life in the underclass. Such character as could be glimpsed was down to some good performances, in particular from Neil Maskell as Carol's terrifying ex, and from Lennie James too, who brought dignity as well as pathos to Richard the ex-junkie, and, of course, from Colman (cursed be her name!).

But blimey, Run was an unremittingly bleak view of society. The most vulnerable citizens seemed bound to one another by little more than sleazy obligations, debts and the necessity to try to look unhappier than the other poor blighter in the room. The writing was undercooked and the direction too quick to lean on the soundtrack's strings section for emotion.

Perhaps the scheduling was also to blame for Run's one-eyed vision. It was, as they say, "stripped" across the 10pm slot on four consecutive nights, and perhaps meant to be regarded as four acts of a single drama. The presumption on the part of schedulers would seem to be that this is must-watch telly; the reaction of viewers – okay, the reaction of me – is "What, again? Tomorrow night, and the night after and the night after that!?"

I'm not sure why Christopher Guest is making sitcoms for the BBC – I hope it's not because he can't get any money to make the sweet and funny films that invented the "mockumentary", Spinal Tap, Best in Show, A Mighty Wind. Either way, Family Tree (BBC, Tuesday ***) didn't get off to a convincing start on Tuesday. Again, it's a mockumentary. This time the idea is that we're following Tom (Chris O'Dowd), recently dumped and newly unemployed, as he, um, becomes interested in his family's genealogy. Yes, it's quite slight. Among the virtues of Guest's films is the authenticity of the sub-cultures under scrutiny. Here, the pretext for Tom's mild odyssey was pretty flimsy.

There were some customarily silly names: Glenn Pfister, Pete Stupples. There were some nice lines, too: Tom's best friend says of him, "I'm a man who enjoys PlayStation in his pants, but five days is, like, two days too long". There was also the wonderful ventriloquist Nina Conti, complete with monkey puppet throughout (even if she did play an annoyingly twee version of herself). Yet finally there was the question as to how Tom, an affable, sensible former civil servant in his thirties with an ex-Beefeater for a father – rather than, say, an indulgent investment banker – was content to gad about happily looking for his ancestors? But I judge too early, it is the first episode after all.

And what is Christopher Guest if not a harbinger of fun?