A naive single mom (Anna Kendrick) and a secretive fashion marketing whiz (Blake Lively) whose sons are classmates become afternoon-martini friends. When Lively abruptly disappears, Kendrick goes all Nancy Drew to find her. The film’s elaborate twists and turns are amusing, until they’re not. Paul Feig’s (Bridesmaids) venture into thriller intrigue is plagued with huge tonal swings and unnecessary third-act complexity, and neither actress quite succeeds in selling the increasingly disturbing concepts. It’s a consciously campy, above average popcorn flick, but I left the theater unsatisfied. (117 min)