The late 1970s were a time of moral ambiguousness in America. Symbolizing that era are the morally ambiguous protagonists of “The Nice Guys” (2016). Ryan Gosling (drunken detective but well-meaning single father) and Russell Crowe (sadistically violent goon with a heart of gold) team up to crack a murder case. Hijinks ensue. There’s lots of people accidentally getting shot (yet when people shoot at each other on purpose, they’re always missing). There’s also lots of era-inappropriate speech and items (crime-scene tape in 1977?), and other terrible production values (leisure suits that go from soaking wet to bone dry in minutes).