I'm always very aware of the physical challenges of work. I train much more than I did when I was in my twenties, and I've done some very physical films, and I always get properly prepared for them and get as fit as I can.

I just like to keep challenging myself, keep it varied. It's a craft, and I'm constantly trying to learn and get better at it.

When you're doing those operation scenes, you not only have to be on top of the dialogue and the rhythm of the dialogue and what's happening dramatically, but you've got to technically get the rhythm right, so that everything is fitting with the dialogue at the right time. And you're performing the operation to the audience that's watching it. Thackery has to present it, as well. In some ways, that's the most challenging.

The medical operations are so challenging because they're so technical, as well. I assumed before we started that we would do the classic thing, when it comes to the operations, that we would do all of these inserts with real doctors.