With apologies to Jean-Luc Godard, all you really need for a movie is a girl and a shark. In Jaume Collet-Serra’s 2016 The Shallows , Blake Lively plays Nancy, a surfer who has trekked to a remote dream beach in Mexico to ride the waves. (The film was actually shot on the stunningly verdant coast of Queensland, Australia.) The secret beach was her late mother’s favorite place; a friend who was supposed to accompany her has dropped out. No worries: Nancy is experienced enough to surf alone, as