What a strange, shape-shifting thing Luther is. Storylines ebb and flow around Idris Elba's dauntingly huge central character like flotsam and debris borne along on a heaving swell, but the man himself wades imperiously through it all like the Colossus in an old Jason and the Argonauts movie. Gross professional misconduct, subterfuge and blatantly aiding and abetting criminal behaviour are all part of Luther's daily routine. It's quite easy to forget that he's supposed to be a copper.

Mainstream television drama has always shone a searching beam into the Stygian murk of society’s ills. But however laudable its campaigning credentials, a drama’s first duty to its audience is to work as drama. Cathy Come Home changed the public perception of homelessness, unemployment acquired a catchphrase in Boys from the Black Stuff, and institutional racism met its match in The Murder of Stephen Lawrence. But we know them first and foremost as great television.

Fake or Fortune? on BBC One, with Fiona Bruce and art dealer and sleuth Philip Mould, ought to have been called CSI: Cork Street for its blend of fine art and forensic science. They were trying to resolve whether a Monet was in fact a Monet, using a 240 million-pixel camera, Monet's own accountbook (which Fiona Bruce ran her ungloved fingers across) and plenty of ominous music. Next up: who killed Marat in David's picture?

A year ago when Luther battered down the door like a wailing banshee in bovver boots on day release, it was all a bit underwhelming. People shrugged and wondered whether Idris Elba was condemned to roam in eternal script limbo. They weren’t at all sure about Ruth Wilson’s parricidal astrosphysicist, all beestung, flame-maned and frog-boxed.

Thanks to her evergreen bestseller Behind the Scenes at the Museum, Kate Atkinson can call on an army of fans to buy her work whenever it appears in print. Its debut on screen is, perhaps, another matter. Will they buy the BBC’s rendition of Case Histories? Those who have not had the pleasure of reading it are less advantageously placed to grumble about hideous revisions, outrageous changes and all manner of infidelities. But even an Atkinson newbie might find it a bit rum that Scotland seems to be entirely populated by people with English accents.

Crikey, no gongs whatsoever for ITV1's Downton Abbey, but you can't grumble about Sherlock lifting the Best Drama Series award at last night's Baftas. Steven Moffat and Mark Gatiss's ingenious update of Conan Doyle for BBC One was one of 2010's telly highlights, and you might have thought it would have earned the Leading Actor award for Benedict Cumberbatch.

Oh joy upon joys, as The Apprentice returns. Those of you who watch while playing a drinking game in which you imbibe every time a cliché or preposterous, bombastic or ridiculously inflated statement is uttered will have to check in your livers again sometime soon, but I’m delighted to say that this new series allows another permutation of the game - have a glug every time you can spot the person who has watched every second of the previous six series but Hasn’t Learnt a Damned Thing.

In a week unfeasibly packed with new drama across the BBC and ITV, the three-part Exile may prove to be the one that lingers longest. It was a thriller and a detective story, but what gave it its formidable grip was the way the central mystery was intricately entwined with the painful personal story of  Tom Ronstadt (John Simm) and his father Sam (Jim Broadbent).