Rafe Spall (“Prometheus”) and Megan Park have joined the cast of Michael Dowse’s romantic comedy “The F Word,” opposite Daniel Radcliffe, Zoe Kazan, Mackenzie Davis and Adam Driver.Lensing is starting this week with shooting set for Toronto and Dublin. Radcliffe and Kazan star as twentysomethings who meet at a party and hit it off, despite the fact that she has a long-term boyfriend, portrayed by Spall. Davis Gross is producing with Dowse directing from Elan Mastai’s script. Jesse Shapira is exec producing. “The F Word” will be released by eOne in the U.K. and Canada. eOne Films International will sell the film in the rest of the world except in the U.S., which will be handled by UTA and Jamie Feldman.