I change myself a lot. Some roles you don't want to be big, bulky, muscle-y guy and some roles you want to be a lean, marathon-runner physical type. And some roles you just don't want to be in shape.

I had done a little bit one other time. This character [in Jack Reacher] is a psychopath, but I had been hired by Carlton Cuse and Randall Wallace.

For some roles, like when I was doing Bent, that was harder and I didn't find that helpful because I was so calorie deprived, my brain wasn't getting food. I would end up not being as focused or as clearheaded as I would have liked to be during the run of the performances. I would lose those quality impulses that you lean on when you're acting because of malnutrition. basically. But I looked skinny.

Obviously I was talking to my parents and my girlfriend all the time, but it's one thing to finally be in the same room and get to be with each other and just hang out.

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.

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

[Jack Reacher] is the longest I'd ever shot anything - and let's be clear, this is my first studio feature film - so there was a huge learning curve.