I absolutely don't relate to being beaten down my whole life - I had amazing opportunities at a young age - but there is still in many, many people's minds the notion that I'll never be able to escape Harry Potter.

I was in the bath at the time, and my dad came running in and said, 'Guess who they want to play Harry Potter!?' and I started to cry. It was probably the best moment of my life.

Paul [Dano] was amazing at carrying me around [in Swiss Army Man]. I wanted to be there as much as possible but didn't want to hurt Paul's back, but Paul often chose me over the dummy many times on the set. But yeah, to be honest, a little bit of preparation I did with my friend in my flat could never have prepared me for quite the level of physical reliance we would have on each other.

I think that the process of making a film is an underrated factor in how that film turns out.

I think being on a film set for such a long time made me a technical actor without realizing it.

I basically have the diet of a 19th-century Irish navy, apart from the litre of stout a day. It's meat and potatoes and bread and cheese: those are my four food groups.

I pretty much left full-time, formal education when I was 11. So that was when I was taken out of the school system... I think the longest stretch I would go back for was a term and a half when I was about 14.