The Big C, More4

Probably the only person who would try and tackle cancer in a "humorous" way in Britain would be Frankie Boyle, and God knows he's not funny. No doubt we'd be treated to jokes about how unattractive women without hair are, or something equally enlightening.

Laura Linney, saddled with infantile Oliver Platt as a husband and a son who seems on the cusp of rebellion, gets X-ray results with those ominous black spots, and it's terminal. Her almost immediate response is to unchain herself from the bonds of boredom she has created for her life, demanding a swimming pool in her back garden and making contact, for the first time, with her cranky, ancient neighbour (a ratty, smoky-voiced Phyllis Somerville). She orders four types of dessert and chucks out her husband.

This sort of reaction is wholly understandable, and Linney conveys the madcap joy of it, daring to say that cancer can be a liberation. But sometimes when she smiles, her eyes show something else, and it is this tension - between telling her family and keeping it secret, between smelling the roses and raging against her fate - which Linney excels at. She is constantly on the verge of a crack-up, but is self-controlled enough (thus far) to withstand it. Linney's performances often manage to contain these contradictory impulses - as Mary Ann Singleton in Tales of the City she was naive and sharp; even in a minor role in Mystic River she was maternal and cruel. The first episode of The Big C gave every indication that her tremendous skill will once again be applied with subtlety.

American TV is regularly sanitised, visually and morally and conceptually airbrushed to within an inch of its existence, so when Lynette gets cancer on Desperate Housewives, it's fairly decorous, she can tell all her loyal friends, who rally round, and she's beaten it within the fortnight. But coming to greater prominence is this sort of half-hour dramedy which deals with difficult issues in unforgiving, or at least un-mawkish, ways.

Take Nurse Jackie, where Edie Falco is a tart-tongued nurse in a New York hospital. Whereas even ER's gunshot wounds were perfectly tasteful, here a man with a hernia has his guts oozing out of his stomach. There is clearly an audience for these topics, but by handling them with humour, they become almost transgressive: not only are we going to talk about cancer, we're going to laugh about it too. And The Big C does have funny moments of all varieties - embarrassing, goofy, cruel.

While the programme is hardly ugly, it takes enough of the gloss off Middle America to make us much more inclined to go with its characters. Linney, for example, can't stop her bathrobe from slipping open, which sounds minor but is just inelegant enough to make her that much more human, confused and even vulnerable. Gone are shiny West Coast tans and smiles and in comes humdrum Minneapolis.

But the last thing that The Big C is is humdrum. Perhaps it will fail to develop with any subtlety or humour, but its serious subject, mixed with enlightening performances, may well continue to compel.