'Based on a True Story': Kaley Cuoco, Chris Messina on How Her Pregnancy Added to the Series (Exclusive)

Following her Emmy-nominated performance on The Flight Attendant, which ran for two seasons on Max, Kaley Cuoco is returning to the world of crime in the new Peacock original series, Based on a True Story. Created by showrunner Craig Rosenberg, the comedic thriller follows a down-on-their-luck married couple who find themselves crossing paths with an infamous serial killer and attempt to turn their fortune around by trying to convince the murderer into doing a true-crime podcast with them.   

"I have a love of true crime. I'm obsessed," Cuoco admits to ET's Cassie DiLaura, revealing that she's "the girl binging 48 hours of Forensic Files and all those things."

On the series, which satirizes the true crime genre and fans' obsession with these types of shows, Cuoco plays Ava, one-half of the killer-obsessed couple alongside her husband, Nathan (Chris Messina), who are expecting their first child -- something that's adding to their desperation to get things in their lives back on track. 

But when the 37-year-old star first signed on to the series, neither she nor her character was pregnant. But much to everyone's surprise, Cuoco found out she was expecting before filming had even started, prompting Rosenberg to write it into the series. 

"I remember when Craig called me and said Kaley's pregnant," Messina recalls, with Cuoco adding that "this was before we talked or ever met yet. Because we would have texted or something." 

"I was like, that is amazing. I mean, obviously, for her life, but just the stakes rise in the show," Messina says, explaining that "they're losing their place in life, losing each other. They don't have money and then here comes a baby."  

"It added so much of the story into the show and it raised the stakes so much more," Cuoco adds. "Obviously, it caught me by surprise to tell everyone and be like, 'What do you think?'" But as it turns out, "they actually ended up being great," she continues, explaining that it added "that one extra thing to cause the amount of stress this couple is going through." 

Not only that, but the stakes are so visual. According to Rosenberg, the pregnancy is just great subtext, making it clear what this new family with money troubles is willing to do to make their lives better for everyone. It also is a constant reminder why they would risk their lives -- or life in jail -- by going so far as to blackmail a serial killer rather than just calling the police. 

But along with the pregnancy came those unexpected cravings, with Cuoco revealing she "pretty much ate anything that was edible" while on set. "I weirdly craved ice the entire time. I just wanted crushed ice, like, aggressively," she shares. "I was always at craft service, and I brought everyone down with me." 

"I also craved In-N-Out," Cuoco says of the popular West Coast fast food chain, before revealing that it was something she also got her co-star into as well. "I introduced Tom Bateman to his first In-N-Out burger, I'd like the world to know." 

And it turns out, the British actor who plays Matt, the smoldering handyman on the series, "loved it," she confirms.   

Cuoco's pregnancy also added a deadline to filming the series' eight episodes. "We were shooting up to, like, three-and-a-half weeks before I had her," she says, referring to her daughter, Matilda, who was born March 30, 2023. 

But her looming due date didn't stop her from taking on any physical activities, with Cuoco challenging her showrunner to some time on the tennis court. "On the last day of shooting, I decided to play tennis with Craig," she shares. 

"He's like, 'Maybe you shouldn't play.' I'm like, 'I'll be fine…' He was so worried about me," the actress adds, before revealing that she's just as competitive as one particular character from the show Friends. "I'm like Monica." 

Luckily for everyone involved, there were no issues on set, with the filming complete before Cuoco gave birth to her first child with partner and fellow actor Tom Pelphrey. And as a result, fans will get to watch her and Messina in what the two describe as a "chaotic," "exciting," "very funny," "sexy," "dark" and "twisted" series. 

All eight episodes of Based on a True Story are now streaming on Peacock.

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