Here's Sir Ian McKellen's 93-year-old Sherlock Holmes

SIR Ian McKellen has posted a Twitter picture of himself as a nonagenarian Sherlock Holmes in the upcoming film Mr Holmes.

Previously titled A Slight Trick of the Mind and based on a novel by Mitch Cullin, the film will follow the detective in his final years, with the 75-year-old actor being aged further through make-up to play a 93-year-old Holmes.

"Over 70 actors have previously played Sherlock Holmes. Now he's 93 years old and it's my turn. #MrHolmes," McKellen wrote on Twitter.

Set in 1947, the movie sees the detective living out his twilight years in a sleepy Sussex village his housekeeper and her son, haunted by an unsolved case dating back 50 years.

Laura Linney will play the housekeeper Mrs Munro, while Zak Shukor will play a character named Matsuda Umezaki.

McKellen is currently in cinemas as Magneto in X-Men: Days of Future Past, which is breaking box office records for the franchise.

He recently shot down the idea of doing a reality show alongside best friend Sir Patrick Stewart, saying: "I've been asked recently to do a number of things which are not to do with acting, particularly on television - presenting and so on - that's not what I really do best or what I want to do."

He added to Entertainment Weekly: "I enjoy acting. I wouldn't want to become a TV bore, who turns up everywhere on chat shows and quiz shows and documentaries and so on. No, I think I'll stick to being an actor."