When I came on to Jack Reacher, I had just taken my girlfriend on vacation and ate everything I could. I put on about 15 pounds, so when I met [the Jack Reacher team] I was clocking in at about 180. They looked at me and were like, "You're just gonna lose five pounds, we're gonna keep you skinny".

When I did Casual, I just let myself put on weight because he's a schoolteacher. He's not meant to be muscle-y.

I had just come off of doing a play in Los Angeles which actually got me the role. It was called Bent and it was at the Mark Taper Forum. I was playing a homosexual in 1930 to 1934 Berlin who is eventually put into a concentration camp for the second half of the play. I had lost about 38 pounds for that.

You get a role like this in a big action movie [like Jack Reacher] and you can go one of two ways: you can paint in broad strokes, which happens a lot in action films, or you can get very detailed.

Psychopaths don't have that charming skill set. They definitely manipulate, but they do it through focused, unskilled means. They're more obsessive.

Sociopaths are more complicated psychopaths; the difference between a sociopath and a psychopath is a sociopath is incredibly charming. There are a lot of sociopaths that are CEOs. They don't necessarily kill people but they're able to walk into a big social function and make everybody think they're the kindest, coolest, smartest, most interesting person in the room.

I'm a trained actor and I can always tone it down, I can always simplify the work I've done. But if I'm asked to bring the nuanced and complicated work, I'll have it in my pocket, and all that information helps.