It’s official, screen legend Ian McKellen has signed on to play a retired Sherlock Holmes in Bill Condon's A Slight Trick of the Mind. The movie is based on a novel of the same name by Mitch Cullin while the screenplay is being adapted by Jeffrey Hatcher. Anne Carey will produce.

The plot: a retired Holmes racks his brain for the answers to an unsolved case 50 years prior. His brilliant yet fading mind can’t handle the lack of closure, so, stripped of his once-impenetrable logic, he sets out on his hardest case yet.

It’s not often you can say this about a role – just ask the fans of 50 Shades of Grey – but McKellen is literally perfect to fill this role. Credits for that sentence go to the Oxford online dictionary for changing the meaning of “literally.” But, jokes aside, we can’t think of a better man to take on the part.

Condon is currently in Toronto for the world premiere of his latest film The Fifth Estate - the tale of the rise and fall of Wikileaks and its founder Julian Assange, played by Benedict Cumberbatch.

Carey said: "Mitch Cullin's elegiac novel is not so much about solving a mystery, as it is about accepting life's mysteries. I could not be more excited about the talent who have come together to make this film a reality." Giladi described Condon and McKellen as "a perfect match for this clever and intriguing project. (THR)

Come on, you impatient fools: there’s no release date yet, but filming it et to start in April 2014 in the U.K.

Ian McKellenSir Ian McKellen is an adored actor