Hidden Lives: Muscle Power (five, 9pm), New Tricks (BBC1, 9pm), Diamond Geezer (ITV1, 9pm).

WE are in a London hotel bedroom where a 39-year-old bus driver from Bristol is lying on the bed. A very muscular woman in a bikini has wrapped her legs around his head. He seems to be enjoying the experience.

No wonder, he's paid the equivalent of a week's wages for an hour-long session with Norwich-born Gayle Moher. She belongs to a rare breed, being one of only 70 professional female bodybuilders in the world.

Anyone anticipating Hidden Lives was going to be about female bodybuilding is going to be disappointed. The makers are more interested in the strange phenomenon known as muscle worship, which involves people parting with their hard-earned cash in order to spend time with Gayle and fellow bodybuilder Lauren.

During what Gayle terms "appointments", there may be touching, kissing, massaging and even the occasional wrestle.

Parcel sorter Daniel has spent £30,000 on sessions and gifts over the past five years. He makes the four-hour trip to London to see her, although it's a lot of time and money just to be sat on by a woman with big muscles.

During their two-week muscle worship tour of Europe, Gayle and Lauren double up for Luca, a 31-year-old university lecturer who says these sessions are "the best way to express my erotic interest in women". Seeing his weedy figure, stripped to his underpants, as the filling in a sandwich between two beefy women, is a disturbing sight. The women can console themselves with the knowledge that their two-week European tour earns them $10,000 dollars each.

The duo also supplement their bodybuilding competition winnings by making videos to sell online, with titles like Machine Gun Divas. These seem to involve the two women striding around in bikinis flexing their considerable muscles.

After all the jollity, the documentary delivers a kick in the stomach by revealing Gayle's role in a tragic shooting before she turned to bodybuilding. It doesn't take a psychiatrist to see that incident played a key part in shaping her life now.

The bodies in New Tricks, returning for a fourth series, are showing signs of wear and tear. With the episode entitled Casualty, you could be forgiven for thinking you've tuned into another BBC1 show.

Amanda Redman's Sandra Pullman is left to run the unsolved crime and open case squad as her three detective sidekicks of pensionable age are in hospital following a car crash, itself triggered by one of them wanting revenge for his wife's death in a hit-and-run incident. They pass the time in their hospital beds by reviving a case from ten years ago when three men died in the hospital on the same night.

New Tricks ambles along - it's hardly going to run with three elderly cops as its heroes, is it? - pleasantly enough, depending heavily on Redman doing her stern boss impersonation and the trio of old coppers (James Bolam, Dennis Waterman and Alun Armstrong) milking every joke imaginable about getting old.

Whether their combined age is enough to beat "the nation's favourite actor" - that's David Jason in case you haven't read the Press release - remains to be seen. Curiously, his new vehicle, Diamond Geezer, is a quaintly old-fashioned crime caper that might come from the British film industry of half-a- century ago.

Jason's criminal Des is more of a comic villain than a nasty piece of work. I'm sure he'd want to be described as lovable as he assumes disguises, most of which wouldn't fool a blind man, to carry out his robberies.

The opener - the first of three following a successful film two years ago - finds him planning to rob Buckingham Palace, not to steal the royal corgis and hold them to ransom, but to remove a very large diamond before it's handed over to the Indian government.

This involves Jenny Agutter as an unlikely journalist and George Cole as an elderly getaway driver (who'd be more at home in New Tricks). It passes 90 minutes harmlessly enough but Des, I would suggest, is unlikely to achieve the cult status of Jason's previous creations, Del Boy or Jack Frost.