Here are eight things you need to know:

1. Wes Knew He Was the Killer All Along. You read that right. Ryan Murphy normally doesn't tell his cast anything when it comes to those major reveals, but he made an exception this time, and for good reason. "In my initial meeting with Ryan," Wes explains, "he just said I'd be a detective who lost a kid. And we talked a lot about losing our kids and that fear, but he never mentioned I was the killer. And then I received the first three scripts as we were gearing up to shoot and I had all these questions and I was texting him. I just felt like there were things I needed to know. At first he was texting me back and then he stopped texting me and he called me a day later and said, ‘OK, listen, I wasn't going to do this and don't tell anybody else that I told you this, but I gotta tell you: You're the guy. Now I don't want you to play it. I just want you to know it so that when moments come up, you'll just subconsciously play it. So it will be good for the show when people know and they look back on it.' I played it as John, as we know him, which is that he didn't honestly know who he was, but we could have those moments like the first time coming to the hotel in episode one, there's a moment where he shares some familiarity with Kathy [Bates] but he doesn't know why. She's like an old friend or somebody you knew long ago. So it's entertaining to look back on, but I never consciously played it. I never thought about it to be honest.

2. Wes Didn't Tell a Soul. "They play games on set and the crew would try to guess who it was and I'd play along with them, half trying to mislead them all the time. It's been fun. I never told anyone. Ryan didn't want me to tell anyone. He knew me and he knows I'm not a talker. Not even my wife, I wouldn't tell her."