Is it like a big family reunion having everyone back on set?

Totally. Just for the read-through the other day, it was like, oh, my brothers! We all have a very sibling relationship similar to our characters. Except Nick [Nicholas Braun, who plays Cousin Greg] is in the family more, and Matthew [MacFadyen] is nothing like his character, Tom. Each of us are similar to our characters but turned up 1000 percent. Kieran [Culkin, who plays Roman]'s a funny guy. He'll always be making jokes and he's very smart, very witty. It's one of the joys of doing the job is that we all get along so well.

Do you know what's in store for Shiv this season?

No, it's a bit of a mystery. I could ask, I guess, and they might tell me. But with the first season, I got used to the fact that I didn't know what was going to happen to Shiv, and I kind of liked that. [Creator Jesse Armstrong and his team] have been in the writers' room since July. Their style seems to be getting a clear picture of what they want to happen and then as it unfolds fill in the dots.

I feel like we were only just starting to see new layers of Shiv toward the end of season 1. Can we expect to discover more of her vulnerabilities in season 2?

I think we'll get a good mix of both—seeing the real power of what Shiv is and, because of that, you might see some vulnerabilities, as well. I think the thing that interested me about the character is that she seems so strong and put together but that oftentimes belies a really vulnerable person on the other side of that. I'm interested to see what happens.