Michael Mosley Compares His 'Criminal Minds' & 'Castle' Baddies

Michael Mosley Criminal Minds Everett Lynch Castle 3XK
Q&A
CBS; ABC

Michael Mosley is playing a reformed bad guy — ex-con hacker CM, working with the FBI against a deadly, rogue Artificial Intelligence — on the new Fox thriller Next, but he's had some memorable turns as villains on procedurals.

You might recognize him as the final Big Bad of Criminal Minds, Everett Lynch (who memorably drove around with his daughter's face on the passenger seat), or Castle's serial killer Jerry Tyson, a.k.a. 3XK. Or maybe you know him from his more comedic roles, like Johnny on the EMT comedy Sirens.

Here, Mosley looks back on these memorable characters.

Is there a common thread you look for in your characters?

Michael Mosley: No, not at all. I'm sure there's some viewpoint 30,000 feet up in the air, higher up, that can say that I tend to gravitate towards this or that. I mostly just find something that I'm attracted to. It's just weird. Sometimes you see something and you have a vibe for it, you think, "Oh, I feel like I can do this," but comedy or drama or good guys or bad guys, I like to do all of it.

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And if I've been doing a comedy for a while, like I did Sirens for two years and then I got lucky, I think I did some Castle after that, where I got to play this total nightmare of a dude, and then Ozark called up and they let me come out. When I read the last episode of the first season of that with the baby and the lake and stuff, I was like, "this is crazy," who gets to do that kind of stuff? It's just fun to try to — it's like cooking. I like to have a lot of ingredients. It's fun to do a lot of different types of things.

You played the final Big Bad of Criminal Minds

Yeah, I was really touched that they let me into their sandbox for their final hurrah. The bad guys have the best lines. It's just fun to play bad guys. And that crew, all those people over there are so sweet. They're the nicest group, the most welcoming. They were doing that show for 150 years or whatever over there, so I didn't know what I was walking into. I was like, these people might just hate everything about this thing at this point. But they were so sweet, so lovely, and so generous.

I'd done a movie with Paget Brewster years ago, and so it was good to get to connect with her again. All so lovely, and so grateful.

And Everett Lynch did some crazy things.

It's just insane, it's like a comic book or something, the pinnacle of villainy or something. I couldn't come up with this stuff. They throw you these balls and you just have to take a swing. It was bizarre. I remember when we were doing the makeup and hair and stuff like that, I wanted to make sure we tried to keep it as real as possible. I didn't want this guy to turn into Mr. Potato Head. But it was fun to get to play different characters within a character. It's an actor's dream.

Yeah, and to meet your character in one season, then wait until the finale to see it end and to have him part of the jet blowing up...

Yeah, that was funny, too. They were like, "Oh, you didn't know? Everett knows how to fly." The guy was unstoppable.

You mentioned the "total nightmare" from Castle, and every time 3XK showed up, he had a new game to play with Castle. What stands out to you about that character?

He's a weird one. He's a real psychopath. Whereas Everett Lynch was more of a con man to get to his goals, whatever they were, 3XK was more of a complete absence of empathy or anything. He was like a zero inside, like a void. Everett Lynch would emote. He had feelings. I don't think 3XK did.

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Everett Lynch had to be charming enough to win over these women.

Yeah, exactly, and 3XK I don't think cares about charm.

You brought up Sirens earlier, which was such a fun show.

That was maybe one of the best times I've had in the business. We were in Chicago, in the fall. Kevin Daniels and Kevin Bigley were my two ride-or-dies in the ambulance with me, and we would just crack each other up. Those were my best friends. They'll be my best friends for life, those guys. We just had so much fun, all day.

I found with comedies — it seems like we did the same thing in Scrubs, too, with Bill Lawrence — you do a couple according to the script and then you do three where you just swim around the script a little bit and you think of alt punch lines. Bob Fisher, who was our showrunner on Sirens, he'd be on a walkie in a travel van with us while we're doing the scene in the ambulance and he'd give us alt lines; he'd see us do something and be like, "Oh, this will be funnier."

Michael Mosley Kevin Bigley Kevin Daniels Sirens

Michael Mosley, Kevin Bigley, and Kevin Daniels on Sirens (Chuck Hodes / © USA Network / Courtesy: Everett Collection)

With comedy, I find it's what's funniest floats, and if anybody on set comes up with something that might be a better punchline to something, that seems to end up worming its way into the final cut. Sirens is one of the best times I ever had. I love that show. And Denis Leary was awesome. It's just a good group of people.