Father-daughter has a lot of layers, I find.

I had the feeling I had to stay focused on what's lying under. A big part of the story in Toni Erdmann happens on the sub-level. On the surface, a lot of scenes, it's banal. If the actor starts thinking, Oh, I'm in a genre, I'm doing a comedy, I'm doing funny things, then you lose.

When you direct the dialogue you can be precise, but with a song as a director you're more like a football coach. You can say one, two things in the beginning and then the actor has to follow what happens.

With every enemy, when you get closer you understand much more, or the picture dissolves.

A family is something very static and hard to escape, so everybody has a certain role over the years, no matter if you like it or not.