S tarting as an intriguingly jittery, slow-boil ’70s-set mystery about a gangster’s naive wife forced into hiding with her baby, this stylishlooking piece morphs into a predictable thriller. Rachel Brosnahan (The Marvelous Mrs. Maisel) is excellent as the terrified Jean, who forges an unlikely alliance to bring the fight to her pursuers. But despite its fine period setting (lurid negligees, swirly wallpapers, Chryslers as big as whales) none of it has the verve or pathos of a moll-on-the run classic like Cassavetes’ Gloria.