Michele Hewitson: It's in the blood

Richard O'Brien hosts The DNA Detectives.

It was somebody's stroke of genius to cast the creator of the musical, The Rocky Horror Show, Richard O'Brien, who later played Riff Raff in the film, The Rocky Horror Picture Show, as the host of The DNA Detectives (TV One, Wednesdays, 8.30pm.)

He lends to proceedings an air of utter and entirely necessary silliness - his props are a now antique typewriter and one of those quaint telephones with a dial and a big red button he pushes with gusto to conjure forth the week's celebs.

The celebrities are the ones who have had their DNA analysed (through some arcane magic posing as science) and who the host is about to send out into the world with a "device" with which he will communicate with them.

The device is one of those newfangled things called a smartphone. In addition to the silliness, he is an ever-so-slightly sinister presence.

If he'd been rattling about in your DNA, you might be a bit worried about what he'd find there. He's a delightfully unpredictable character which is perfect for a show which is supposed to reveal skeletons. The skeletons may have, if you are lucky, or not so lucky, royal links. "There are a few queens in my family as well..." said O'Brien.

There were (well, possibly) rivers of blood in actor Amanda Billing's DNA. She may have Viking blood, and we all know what beasts they were. She was sent to, among other places, a nutty Viking museum on the Isle of Man, where the Vikings on exhibit (no, not real ones, obviously; and not stuffed ones, either) appeared to have been modelled on those chaps who appear on the covers of bodice-rippers, with the addition of some very bad wigs.

A weather chap, Sam Wallace, got to go to Sardinia. (It'd be worth discovering any number of bloody rivers or nasty rellies to have your DNA detected by this show - the real purpose is to be sent on a very nice free holiday.)

He had a tiny amount of Italian in his DNA, about the amount, I imagined, having failed School C science (twice), that you'd get from having eaten too many bad pizzas in Hamilton, say. Anyway, a nice jaunt if you can get it. Sam tried a sea urchin pizza, which is a kina pizza with a fancy name. He gave a bit to a small and telegenic dog he'd made mates with. The dog spat the kina pizza out. "Come on, mate," said Sam to the cute dog. "Let's go and get some steak." He was over the moon to spot a Ducati motorbike, the very one his dad had been "dreaming of". So he must be at least half a pizza slice's part-Italian.

He was sent to Scotland where he went to the pub to have a drink with some local William Wallace enthusiasts. William Wallace was Braveheart. He had no children, so no direct descendants, but never mind.

Sam was sent to look at Buckingham Palace. He shares some DNA with Prince Philip. He wasn't actually invited in for tea. That was probably just as well as this may be one of the not so lucky royal links. Would he prove to have inherited a propensity for gaffes? He had said, earlier, that he wondered where his olive skin had come from. Perhaps, he said "a milkman had snuck in there..." That was a bit Prince Philip-y.

Sometimes, if you go ferreting about in your DNA, you might find some nasty surprises. Amanda Billing found a great-great-great grandmother who had been sentenced to life in Tasmania for the "crime" of having been raped by her father. This was a tragic story.

So there are tears and jokes - Sam was sent to stay the night at one of his ancestral castles; it was a ruin on a hill, ha ha - but the show succeeds in managing to get the tone just right. It could feel manipulative and mawkish (and there are a few, probably inevitably, mawky moments) but it doesn't. So good on the makers, and the host, who is fabulously just right.