One is a crazy postmodern comedy about a collection of dolls recognised for their bright pink clothes. The other is a gloomy biopic about the scientist who developed the first nuclear weapon during WWII. One has Margot Robbie and Ryan Gosling singing and dancing on a plastic beach. In the other, a skeletal Cillian Murphy is concerned that he will accidently eradicate the world around him. This is Barbenheimer’s summer.