It's Benedict Cumberbatch Vs. Kate and Wills. And we know whose side we're on.

Benedict Cumberbatch — he of the regal name, curious good looks and multiple Oscar nominations — just got behind a seriously worthy cause.

He’s an activist. A Cumberbatcivist.

The British actor (Cumberbactor), who picked up an Oscar nomination for his role as WW2 code-breaker Alan Turing in The Imitation Game, is fronting a campaign to pardon some 49,000 people prosecuted under historic homophobic laws, which imprisoned homosexual men for so-called “gross indecency”.

The campaign has attracted more than 100,000 signatures on — but two very famous people have royally snubbed it: Prince William and Kate Middleton.

As The Independent reports, the royal couple rejected Benedict Cumberbatch‘s petition to pardon those convicted under old anti-gay laws in Britain. They are now reportedly refusing to comment, citing the issue is a matter for government.

Benedict Cumberbatch as Alan Turing in The Imitation Game.

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The issue of unfair treatment of gay men in Britain was brought to Cumberbatch’s attention during his recent portrayal of computer science whiz Turing, who was prosecuted and sentenced to a chemical castration under the law in 1952, but granted a posthumous pardon in 2013.

Cumberbatch wrote in an email to The Hollywood Reporter that he found the whole issue “deplorable”.

“Alan Turing was not only prosecuted, but quite arguably persuaded to end his own life early, by a society who called him a criminal for simply seeking out the love he deserved, as all human beings do,” Cumberbatch said.

“Sixty years later, that same government claimed to ‘forgive’ him by pardoning him. I find this deplorable, because Turing’s actions did not warrant forgiveness — theirs did — and the 49,000 other prosecuted men deserve the same.”

Kate Middleton and Prince William have refused Cumberbatch’ plea for support

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The petition wants to bring justice to the victims of the law which “brought not only unwarranted shame, but horrific physical and mental damage and lost years of wrongful imprisonment to these men.”

It is also supported by British comedian, actor and activist Stephen Fry.

You can find the original petition here.