We let you know what's going on behind the scenes of ''A Slight Trick of the Mind''

When director Bill Condon asked Laura Linney to star in his new film A Slight Trick of the Mind — starring Ian McKellen as an aging Sherlock Holmes — he hadn’t a clue that he was tapping into her childhood fantasies. “I was obsessed with Sherlock Holmes as a young kid,” says Linney, 50, who’ll play the detective’s housekeeper in the film, which begins shooting this July in London and Sussex, England. “You know how some people are into Dungeons & Dragons? I was into Sherlock Holmes. I loved the atmosphere of the stories. I loved the intrigue, his personality. Bill had no idea.”

It’s surprising that he didn’t: Linney and Condon have been pals since 2003, when they shot Kinsey, which scored the actress her second Oscar nod. Since then they have collaborated two more times, most recently on The Fifth Estate. (That film costarred Benedict Cumberbatch, who, yes, plays Holmes on the PBS series Sherlock.)

A Slight Trick of the Mind, based on the 2005 novel by Mitch Cullin, will bring Linney and McKellen together for the first time. “I’m looking forward to the combined talent, skills, and smarts,” says Condon, who directed McKellen in the 1998 drama Gods and Monsters. “Both of them are incredibly detail- oriented and do an amazing amount of work before they get to set, and then they dive off the board and become their characters.”