Benedict Cumberbatch says his TV alter-ego Sherlock Holmes is too busy investigating mysteries to have sex.

The Sherlock actor revealed his much-loved BBC detective isn’t a sexual being for a reason, because if he got too caught up with the ladies his crime-solving abilities would diminish.

He told Elle magazine: “He’s asexual for a purpose. Not because he doesn’t have a sex drive, but because it’s suppressed to do his work.

“Cold showers, looking at a lot of dead bodies… that’ll do it for you.”

In real life the actor is thought to be stepping out with theatre director and actress Sophie Hunter, who appeared with Benedict in the film Burlesque Fairytales five years ago.

Talking about dating, the actor suggested having a love life as a celebrity can be tough, hinting that some people have only been attracted to his fame.

“It’s a really double-edged sword,” Benedict, 38, told the magazine. “You know, you discover why people find you attractive – in a relationship or a tryst – and if it’s just to have a go on you or try you out, then I can smell that a mile off.”

The actor appears in the December issue of Elle.