'Based on a True Story': Tom Bateman on the Westside Ripper and Making Out With Chris Messina (Exclusive)

Based on a True Story

Bateman opens up to ET about spoilers for the Peacock series.

Warning: Spoilers for Based on a True Story, including the serial killer's identity and other key moments from season 1. 

Now streaming on Peacock, season 1 of Based on a True Story mixes humor with sex and thrills to deliver a witty satire of the true-crime genre. At the center of creator Craig Rosenberg's series are Ava (Kaley Cuoco) and Nathan (Chris Messina) Bartlett, a married couple struggling to keep it together who decide to blackmail a serial killer in order to launch a podcast in hopes of solving their personal and financial problems. 

Known as the Westside Ripper, it's quickly revealed that the murderer terrorizing Los Angeles is a brooding yet smoldering local plumber named Matt Pierce (Tom Bateman), who was hired to do some handiwork at the Bartlett's home while also befriending the couple. Then, it's not long before he quickly upends their lives after they discover his true identity and try to rein in his killings.  

Not long after all three begin recording their podcast do their overlapping lives get even more complicated as Matt starts to play cat and mouse with Ava and Nathan's friends and family, threatens to keep up the killings and navigates the notoriety and fame that comes with being the now-infamous murderer. 


"Oh my god, Tom Bateman," Cuoco says of her breakout co-star, while Messina adds, "So, good. Such a great actor. Really, the hardest part on the show is Tom." 

"I mean, he had to play a horrible human being, [and] at the same time, be charming and sweet and fun and threatening," Cuoco continues, before joking, "And then he had to deal with us two, which is the hardest thing he has ever had to do." 

In fact, Bateman was so good in the role that his wife, Daisy Ridley, really liked his performance. "She was very sweet about it… She said, 'Yeah, I find you creepy in the right amount of ways,'" the 34-year-old British star says. While speaking to ET, the actor opens up about how Jon Ronson's book, The Psychopath Test, informs Matt's murderous ways, if he's really the one behind all the killings and filming those dance floor makeout scenes with Messina and Cuoco.   

ET: What excited you most about the role and getting to play Matt here? 

Tom Bateman: Well, firstly it was the series. When I read it, I thought it was so out of the box. It just swung so big and was unlike anything I'd read. I mean, there's so much stuff that gets made these days that to really stand out when you're reading something is quite hard. But when I read it, I just went, "Oh my god, this show is crazy."

And then when I learned more and more about the character, I just thought, "God, he is so fun." To play a part with someone who's got so many secrets, who's got so much mystery to him is really exciting as an actor because you just got constant levels that you can sort of dial into. The creatives, when I met with them -- [executive producer and director] Alex Buono and Craig Rosenberg -- they were just so up for me playing with different things. 

Also, I read this really cool book called The Psychopath Test by Jon Ronson. And he interviews all these psychopaths. And one of the things he said that really struck him about the people he interviewed was that they wear these masks. He said, "I can't believe it. These people come across as charming and funny and sweet and kind and thoughtful." They remembered his birthday and things like that. And this psychiatrist that he's talking to, she said, "Well, that's what they do…. They have no empathy, so they're very, very good at just performing a role." 

So, when I'm doing scenes with Chris' character, Nathan, I play a certain type of person, and then a different person with Ava, Kaley's character. Anyone he comes into contact with, he's a different person… And the character really required quite a lot of work because we didn't know who this guy was. And I just said, "Look, I wanna just sort of discover this guy." And they were so excited about that. They said, "Look, we just want you to run with this. We want to just sort of create this guy with you." So, that was a very rare and exciting opportunity for me. 

Given all the layers to Matt and the way the story's structured with those fake-out scenes and fantasy moments, did you have an understanding of what Matt's true intentions were or what was real or not with him along the way?

To be honest -- and the fun thing was -- no, I didn't. Even throughout the series, we'd get given the episodes as we were filming and I remember Craig texted me once at about 11 o'clock at night and he said, "I've just sent you this new episode. See what you think." And it was Matt's fantasy sequence in the nightclub where he just kills everyone. I read it and I went, "This is nuts." I didn't see it coming, and it was really fun. Again, that's what's made this so fun to make because every episode I read I didn't see anything coming.


Since you brought up episode five, "Ted Bundy Bottle Opener," I wanted to find out what it was like filming that whole dance floor sequence with Kaley and Chris. 

By that point in the series, we'd been shooting for quite a while and it was a really special experience 'cause me and Kaley and Chris just really clicked into each other and became this sort of three musketeers.

And what was amazing was we had this very, I dunno, it was like a mercurial sort of quality to it, where we all knew each other very, very well. And we just loved each other and respected each other so much so that by the time we came to do this… and we said, "Did you read that f**king episode?" And it was like, "Oh my god, we're gonna go there." But it was super fun. 

Also, it's odd when you do things like that because I said to them on the day, I was like, "Well, we're just spending the day making out with my best friends at the moment, which is an odd thing to do." But again, we all understood the tone and what was happening and we said, "Look, this is just nuts. You wouldn't do this on any other show, so let's just, as we had to do with everything in this year, let's just swing big and hope it comes together."

Well, you know, now I have to ask: Who is the better kisser? Kaley or Chris?

That's hilarious. They're both very, very different. Chris is very intense. He's a very intense kisser.

When it comes to Matt, what excites him more: the notoriety of being the murderer or the fame that comes with the success of the podcast about the murders? Because it does seem like Matt has some stakes in whether the podcast does well or not. 

Oh, 100 percent. And I think what was really interesting, again back to that book that Jon Ronson wrote, one thing that all of these people had in common was this narcissism. They all had this sort of obsession with fame and  having notoriety and having people talk about them. They all loved being interviewed by this amazing journalist. And I thought that with Matt. When we meet him at the beginning, Nathan says, "We're invisible. No one sees us." And Matt says, "Try being a plumber in LA. People just look straight through you." So, I was trying to tap into that, like the beginning of this monster or this predator who cannot tell anyone about these things and how it must be so frustrating. Everyone's talking about this Westside Ripper, but you are powerless to be able to say, "This is me." But the podcast allows him to access this fan base and really sort of validates him as a person and he sort of really gets off on it.

What was interesting was halfway through the series, sort of tapping into that idea that this is exciting and fun and new for Matt because he gets to talk about this stuff and not only do people hear it, but they love it. They can't get enough of it.

But then again, what defines Matt is not talking about these murders. It's doing them. So, it was an interesting pull that after that initial excitement of being on the billboards and getting a bit of money and getting famous, he starts to feel like a caged animal and it's a cage of his own making and he just wants to break out of it and carry on doing the evil things he does. 


Well, that more or less answers my next question, which is whether you think Matt really is the Westside Ripper because there are theories that since we don't see him really killing that many people, he may be taking credit for something he's not actually doing.

Well, it's interesting because there is that point in episode four when he says, "We can claim a few of my own," which was an interesting character beat for me 'cause I thought, "I'm not sure this guy would want to do that." But I guess it's key at that point. He's focused on the success of the podcast.

But I do totally believe -- and my interpretation of the character is -- that he is the serial killer. He is the Westside Ripper. But obviously the show does sort of take it in an unexpected direction that actually for a long period, quite a few episodes, we don't see him do anything. We don't see him commit any murders until Ruby Gale [Priscilla Quintan]. And that's more to help us all out. But at the same time, he's flexing his muscles. 

But it's certainly something that I think -- should we go into a season 2 -- would be a more interesting avenue to explore. Also it's interesting what happens to Nathan and Ava. Because for a long period, they're not scared of Matt and they're teaming up with him. And he hasn't committed these murders. And I think it would be quite an interesting road to go down to see if they are really gonna stay in business with this guy if he starts murdering people regularly.

One of the big revelations we learn in the finale is that Matt and Ava's sister, Tory [Liana Liberato], have been sleeping together. Is this relationship legitimate, or just another way of him messing with Ava and Nathan? 

I mean, it came out of left field for me. When we read it, I texted Liana and said, "Have you read the new episode? I didn't see that coming." But Craig has very cleverly plotted that from the beginning. There's a flirtation there. And I read it as just, you know, "Keep your friends close and your enemies closer." 

Also, he starts to see that Ava and Nathan are starting to get a bit of cold feet and pull away from him. So, what can he do, right? Matt's just gonna really get into their home life. He's gonna really cement himself in there by seducing one of their family members.

It's interesting, like, I'd love to see in season 2 where that goes because he's almost behind enemy lines. And then it's like, "What do they do? Because how are they gonna tell Tory she can't date this guy? They can't tell her the truth. So, it's a really interesting narrative device that I think Craig has put in there. It's totally unexpected and I would love to see where it goes. 

Based on a True Story is now streaming on Peacock. 

[This interview has been edited and condensed for length and clarity. Reporting by Cassie DiLaura and Stacy Lambe.