Mann is a first-time screenwriter; Moverman has done some wonderful, flavorful work in the past, with “The Messenger” and “Love & Mercy” and other projects. Here all is neat and tidy. Much of “Puzzle” feels schematic and, in the convenient solution to the family’s financial problems, a bit lazy. Yet Macdonald is so good, on her own or with a scene partner, director Marc Turtletaub’s movie refuses to fall apart. Macdonald and Khan do their best work in the early scenes, when these opposites have only begun to attract. The imperious Khan complements the piercingly true Macdonald, who has a dazzling way of getting to the heart of her character’s feelings non-verbally, a millisecond after a line of dialogue.