Benedict Cumberbatch has signed an open letter calling on the British government to formally pardon tens of thousands of men who were prosecuted for being gay under old "gross indecency" laws.
The British actor, who played gay codebreaker Alan Turing in the film The Imitation Game, is among more than 40,000 people who have signed the letter printed in the Guardian, calling on the royal family to back the campaign to pardon convicted gay men.
It's estimated that 15,000 men who were convicted under the old law are still alive.
The letter reads:
The UK's homophobic laws made the lives of generations of gay and bisexual men intolerable.
It is up to young leaders of today including the Duke and Duchess of Cambridge to acknowledge this mark on our history and not allow it to stand.
We call upon Her Majesty's government to begin a discussion about the possibility of pardoning all the men, alive or deceased, who like Alan Turing were convicted.
However, a spokesman for the Duke and Duchess of Cambridge told the British media that issue was a matter for the British government, and the pair would not be commenting publicly.
Turing committed suicide in 1954 after he was convicted of gross indecency two years earlier. Members of his family are also among those who have signed the letter.
In 2009 the British government issued a formal apology to the Nazi codebreaker and he was officially pardoned by the Queen in 2013. The campaigners want the same treatment extended to the other gay men convicted under the law.
Actor Stephen Fry, who portrayed the playwright Oscar Wilde in the 1997 film Wilde, has also added his name to the signatories. Wilde was imprisoned in 1895 after being convicted of gross indecency.