So Monroe reached the end of series one, and I still couldn't read what its tone was supposed to be. Some artsdesk readers have expressed enthusiasm for the theme tune, but I find its jogging Celtic jauntiness symptomatic of Monroe's wider problems. Obviously you can't expect too much from a bit of title music,  but surely it should give you a clue as to whether the show is a hard-hitting drama about life and death or a sitcom?

There is an intriguing heresy planted several paragraphs down in Adam’s review of Lewis, which resumed last night on ITV. “It’s the relationship between Lewis and Hathaway that makes the thing worth watching. In fact, it sometimes seems more interesting than the slightly ponderous master-and-servant routine Lewis used to go through with Morse.”

Read Adam Sweeting's review of "Intelligent Design", the last-ever episode of Lewis

It'll be interesting to see what the recent race row - or more accurately, lack-of-race row - does for the ratings of Midsomer Murders. Possibly nothing, if the research that says that people from ethnic groups all hate the show and never watch it is to be believed. It certainly defies logic that producer Brian True-May has been made to walk the plank for saying that the programme has an all-white cast when... it does. Somehow, everybody has contrived not to mention this ever since Midsomer began in 1997.

James Nesbitt has always looked full of himself and too bumptious for comfort, so who better to play a smart-arse neurosurgeon who prides himself on his rock-steady hands and steely nerves? "What really matters is how well you handle losing," he bragged to his attending team of young doctors as they gathered round the latest sawn-open skull, delivering the line with the air of a riverboat gambler striking a match on the sole of his boot.

Notwithstanding his regrettable central role in the recent remake of Bouquet of Barbed Wire, Trevor Eve is an actor who has improved vastly with age. Once cursed with a kind of shiny smugness, the 21st-century Eve is rougher round the edges and indelibly lined with decades of thespian rough'n'tumble.

What’s with the two titles? A crime drama so good that they had to name it twice? Or couldn’t anyone in production decide which one to ditch? Why not swap them around, or maybe call it "Prime Suspect", or "Prime Suspect: Deadly Intent", or variations thereof? (OK, perhaps not "Prime Suspect: Above Suspicion", which would kind of cancel the other one out, but you get my drift.) Indeed, Lynda La Plante’s titles are so irritatingly, meaninglessly generic that they’d fit just about any old plot with a vaguely criminal theme. But then, her plots are generic, so I suppose as long as they’ve got cliché written all over them you’re OK, because at least then you’ll know what complete toss and nonsense to expect. And not even enjoyable toss and nonsense.

“Television is pretty awful at the moment,” said Eileen Atkins the other week. “Is that because I'm getting old?” Age wouldn’t dare to wither Dame Eileen, of course, who has just bounced back in fine sparky fettle in the BBC's remake of Upstairs Downstairs.

If there’s one thing the British love on television at Christmas time, it’s a period drama, and even better, a period mystery. So what joy when there’s a bit of sleuthing by Agatha Christie's yin to Hercule Poirot’s yang, the eagle-eyed wise old bird Miss Marple, in The Secret of Chimneys.

Miss Marple (Julia McKenzie) is asked by Lady Virginia Revel (Charlotte Salt), the daughter of a dead cousin (what a lot of those the old girl appears to have), to be part of a lavish weekend party at the family’s country pile, Chimneys. The house was once known for its society gatherings until a rare diamond was stolen at a party in 1932, a theft that led to the end of Virginia’s diplomat father’s (Edward Fox) career.

The action starts 23 years on, when the world has changed and Chimneys is now too expensive for the family to maintain, but the ambitious and very dull politician George Lomax (Adam Godley) has offered to save it if Virginia, by some years his junior, accepts his proposal of marriage. Trouble is, she has just met and fallen in love with the dashing young Anthony Cade (Jonas Armstrong).

This being Agatha Christie (or at least a very loose adaptation, as she never appeared in the original story), those aren’t enough strands for us to unravel when someone is found deaded, in this case a mysterious Austrian Count (Anthony Higgins) who has specifically asked for a major international trade deal brokered by Lomax to be signed at Chimneys. There’s the chippy Miss Blenkinsopp (Ruth Jones), for one, from the newly created National Heritage who is very keen to get her hands on the property and is found snooping in the library; civil servant Bill Eversleigh (Mathew Horne), another would-be lover of Virginia; Virginia’s unmarried older sister, Bundle (Dervla Kirwan); and the family servant, Tredwell (Michelle Collins), who, Miss Marple soon realises, Has A Secret.

Chief Inspector Battle (Stephen Dillane) arrives from Scotland Yard to investigate and enlists Miss Marple’s help, but then two more deaths occur and lots of red herrings are released into this particular pond. The complicated plot includes a cache of love letters, coded messages, the cover-up of a death long ago and not one but two people with gambling debts.

As we eventually find the dastardly murderer, it all adds up to some nice light entertainment, of course, but by golly I wish everyone involved in The Secret of Chimneys could have given it even the faintest whiff of urgency. The feature-length episode was wonderful to look at, but I’m afraid both Poirot and Marple mysteries on ITV now appear to have taken over from The Bill as the common entry on all British actors' CVs; nice little earners where they galumph about pretty locations and spout trite dialogue as they wait either to be bumped orf or reveal the reason they committed the murder.

Few actors in The Secret of Chimneys appeared to have invested even a minimal effort in their characterisations. Edward Fox, we all know, has been playing variations on his most famous role, the Duke of Windsor, for some time now (the BBC missed a trick in not asking him to appear in the updated Upstairs Downstairs, set in the mid 1930s), Charlotte Salt’s accent was nowhere near posh enough (in contrast to Dervla Kirwan’s spot-on "frightfully"), Michelle Collins was miscast and, fine actress though she is, I think Julia McKenzie is too young and sprightly for Miss Marple.

Perhaps I spent too much of my youth reading Agatha Christie, but I remember her books being page turners; here the story dragged and by the end I didn’t care who had bumped off the Count. Full marks to the location, wardrobe and make-up people, however, as not a cuff or coiffure was out of place.