The Little House, ITV1, Monday<br/>The Trip, BBC2, Monday

Francesca Annis conveys menace bordering on horror in a breathless thriller

Blonde, blue-eyed and vulnerable Ruth (Lucy Griffiths) is married to young, wiry construction whizz Patrick (Rupert Evans).

They are well-off, childless and enjoy having sex in restaurant lavatories. Ruth's an orphan, but the memory of her parents' death in a car crash has been partially occluded by the attentions of her fond in-laws, Elizabeth and Frederick, who are so benevolent, they buy them a little house close to their own. There's only one problem: Ruth's mother-in-law keeps radiating menace at her.

"Patrick needs a good home-cooked meal," says Elizabeth, implying that his wife is starving him. The young couple, she says, could go and look at the new house after lunch, "if Ruth [snarl] doesn't mind". At a boring family Christmas, she tells the quaking girl, "I thought you were harbouring a little secret," and when pregnant Ruth's waters break, "Little Ruthie's going to have our baby."

The fact that Elizabeth is played by Francesca Annis, a great beauty for most of her career, but transformed here into a cross between Cherie Blair and Ursula the Sea Witch, is also alarming. After the birth of young Thomas, things get worse. Elizabeth sneaks random casseroles on to Ruth's kitchen hob. Patrick becomes ever more useless and mother-pecked. He and his parents seem to be in cahoots against the hapless new mother, who takes up smoking and pouring her heart out to a stubble-chinned fellow teacher with an unrequited crush on her.

The baby refuses her nipple and cries all the time. Is it in on the conspiracy? Just when we think we're watching a satanic drama called Ruthie's Baby, directed by Roman Polanski, Ruth spots her mother's ghost strolling in the woods in a peasant headscarf. Is she coming with a message from beyond the grave? Suddenly we're in Don't Look Now territory. A friendly shrink diagnoses post-partum psychosis. Moments later, the baby is found burned by a cigarette while his mother is in the garden, Ruth can't voice her suspicions about Elizabeth and suddenly the in-laws are steering her to an asylum ("We've found a private clinic with beautiful surroundings") while they carry off the baby in triumph ....

The Little House takes some liberties with the excellent thriller by Philippa Gregory, making Ruth a teacher rather than a journalist, and turning Elizabeth into a deranged Medea from the outset. This is supposed to be a slow-burning psychic chiller full of believable people going mad while acting for the best. The TV adaptation piles suspicion upon menace upon horror and gives you no time to breathe. I'll be back for the second half, even though it's been mostly spoilt by an extensive trailer.

I don't think I'll be rushing back to The Trip, which started its six-episode run on Monday. Those who've seen Michael Winterbottom's film A Cock and Bull Story, a surreal treatment of Laurence Sterne's Tristram Shandy, will recall the droll rivalry of Rob Brydon and Steve Coogan, playing themselves when the periwigs came off. Watching Coogan's face as he realised Brydon could do a better impression of him than he could of himself was priceless. Winterbottom now films the two funny men going on a road trip in a Land Rover. Coogan has invited Brydon to join him on a one-week restaurant tour of the North for a Sunday newspaper. He needs a companion because he's split from his girlfriend, Mischa.

So here they are, our gigglesome pair, at The Inn at Whitewell, booking in and – oh no! – there's only one room and they may have to share a bed! Brydon is fine about this. Coogan isn't. "You might touch my bottom," he says. They joke about child abuse, swap photos of their children (not at all inappropriate) and compete, over dinner, to see who can do a better Michael Caine impression. Some needling between them goes unexplained. Coogan doesn't seem to like Brydon much, and criticises him a lot – so why has he invited him on the trip? But the conversations are so desultory, and the straining after wit ("Is there such a thing as an autistic impressionist? That's you") so plain dull, you feel they deserve each other's leaden company. I can't wait to read the restaurant reviews.