Toronto: Ian McKellen to Play Retired Sherlock Holmes in Bill Condon's 'A Slight Trick of the Mind'

The Oscar-winning writer and director collaborated with the actor on "Gods and Monsters" before later working on the last two "Twilight" films.

TORONTO – Oscar winner Bill Condon is to direct A Slight Trick of the Mind with Ian McKellen to star.

The film details the story of a long-retired Sherlock Holmes haunted by an unsolved case from 50 years ago. He remembers only fragments: a confrontation with an angry husband, a secret bond with his beautiful but unstable wife. With his legendary mental powers on the wane, and without his old sidekick Watson, Holmes is faced with the toughest case of his life.

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Based on a novel of the same name by Mitch Cullin, the screenplay is being adapted by Jeffrey Hatcher (The Duchess).

AI Film, the production arm of the Icon U.K. Group owned by Len Blavatnik’s Access Industries, has boarded the project and will finance and co-produce.

Set to shoot April 2014 in the U.K., the film will be produced by Anne Carey through her new venture, Archer Gray Productions.

Says Carey: "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."

Producers of the Oscar winner The King’s Speech, Iain Canning and Emile Sherman of See-Saw Films will produce, with Icon/AI Film CEO Aviv Giladi and Blavatnik as exec producers.

Christine Langan, head of BBC Films, is an exec producer for the public broadcaster's stand-alone moviemaking unit, which is also co-financing.

Condon and McKellen previously worked together on the Academy Award-winning Gods and Monsters, which Condon wrote and directed, and which won the best screenplay nod. Giladi described Condon and McKellen as "a perfect match for this clever and intriguing project.

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

FilmNation Entertainment will handle international sales of the film.

It marks the third project on AI Film's slate. The banner is also co-financing Martin Scorsese's Andrew Garfield and Ken Watanabe starrer Silence with Emmett/Furla Films, Corsan Films and IM Global. Also in the A1 pipeline is co-financing and producing duties on a musical event film chronicling the journey of pop music legend Elton John.