City By the Sea is a father-son story in the trappings of a police drama. Robert De Niro plays a cop whose son, guilty of less than he's suspected of, is on the run from the law. Predictable complications ensue; it's not the story that's interesting here so much as De Niro's complex performance and the film's understanding of human relationships. For such a routine plot, there's a lot going on underneath the surface.