The Midnight in Paris costars were snapped holding hands as they enjoyed a Sunday stroll through the College Street area in Toronto.
Not that their relationship was especially secret.
McAdams, 33, and Sheen, 41, who met on the Midnight in Paris set, have been spotted getting cozy the last few weeks, including at the film's afterparty during the Toronto International Film Festival.
This isn't the first time the dapper Welsh actor, who is best known for his roles in The Queen and the Twilight series, has stepped out with a beautiful actress. He and former girlfriend Kate Beckinsale have an 11 year-old daughter, Lily, together.