There's a lot of work that needs to be done, and there's a difference between talking the talk and walking the walk.

People tell me I look mournful. They say, "Cheer up, Dan, it's not that bad!" Sometimes, I just look into space, which freaks people out. If I was ever required to do anything other than look haunted, I could. I'm a happy person.

If you're on a date and somebody comes up and says, "Oh, I loved you in Harry Potter," it's a bit weird, because you suddenly start thinking, "Oh, God. Is this weird for the other person I'm here with, or is this weird for my family?" But generally speaking, I don't really think because I was thrown into it so young and kind of always had that, it's just something you get used to. And most of the time... It was interesting.

The best thing I've learned is, if you're going out, never go out alone - you leave yourself vulnerable. If you've got someone else there you trust, they can say, be wary of that person. I probably used to be too trusting of people.

I think it was pretty obvious early on that we had both come with kind of the same attitude of "Let's just [jump] in," and neither of us was going to be precious about it. I feel like the thing that we learned is, weirdly, the most intimate thing or a very intimate thing you can do to somebody is hold their tongue with your fingers. When Paul [Dano] is making me talk [in Swiss Army Man].

I will never, ever do a film as successful as the Harry Potter series. But neither will anyone else.

In terms of drama school, what that will give you that you won't necessarily learn on a film set is the technical ability - ie, projecting your voice and stage craft.