This is very disciplined film. You might not think it was possible to make a film about the most famous outlaw of the 1930s without clichés and "star chemistry" and a film class screenplay structure, but Mann does it. He is particular about the way he presents Dillinger and Billie. He sees him and her. Not them. They are never a couple. They are their needs. She needs to be protected, because she is so vulnerable. He needs someone to protect, in order to affirm his invincibility.