This was shot at the legendary Ealing Studios, but I hesitate to call it a British comedy: its two stars are American, it opened in the U.S. five months before it opened in the UK, and its innocuous naughtiness seems pitched at grandmothers who watch BBC America. Frances McDormand plays the title character, a prim governess in pre-World War II London who finagles herself a job as social secretary to a glamorous but dim-witted American actress (Amy Adams of Enchanted). Director Bharat Nalluri tries to goose the bedroom farce with swing music, heavy on the brushes and clarinet, and the blossoming romance between the frumpy Pettigrew and an urbane fashion designer (Ciaran Hinds) seems willfully ignorant of British class codes. Adams, who won an Oscar nomination for her glowing performance in Junebug, is forced and antic here. With Shirley Henderson. PG-13, 92 min.