Since The Big Bang Theory ended its run back 2019, Kaley Cuoco has been busier than ever. In fact, the actress immediately went to work on the Emmy-winning and Golden Globe-nominated series The Flight Attendant, where she serves as both the main star and executive producer.Based on a novel of the same name by Chris Bohjalian, the show centers on Cuoco’s character, Cassie Bowden, a flight attendant who finds herself in a series of misadventures. During the first season, she wakes up next to a dead body. And in the second season (which may or may not be better than the first), she witnesses an assassination while working on her CIA side hustle.RELATED: Why Kaley Cuoco Struggled So Much With This Scene From 'The Flight Attendant'Aside from Cuoco, the series also stars Zosia Mamet who is probably best remembered for her time in the hit HBO series Girls. On the show, Mamet plays Cassie’s best friend, Annie. And with their amazing chemistry onscreen, fans have wondered how close the two stars have become in real life.

The First Time They Met, There Was A Boop Involved

When Mamet first came to the auditions, she had never met Cuoco. However, there she was, about to do a chemistry read with the actress and no one specified how they wanted the scene to play out. Basically, Mamet could play Annie however she wanted as Cuoco did the same with Cassie.

“I walked into that room, and they were like, ‘Feel free to play,’” Mamet recalled. “I was pretending to be on my phone in the audition room, and Kaley walked up and bopped me on the nose, which wasn’t in the script, and I immediately swatted her hand away like ‘Don’t do that.’”

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Swatting aside, the two actresses knew immediately that they would click. “I always say that, in that moment, Annie and Cassie were born,” Mamet remarked. “It was this immediate spark of chemistry between the two of us. … We both just have this great sense of play, and we adore working together.”

They Have Something Else In Common, Besides Being Actresses

Ever since their first meeting, Cuoco and Mamet became besties almost instantly. And while that may be due to the fact that they ended up spending a great deal of time together, it may also be because both actresses share a love for horses. In fact, it is believed that Cuoco now owns as many as 25 horses. Meanwhile, Mamet is a proud mom to her thoroughbred, Ten.

And of course, horse girls always stick together. “We text about horses constantly,” Mamet revealed. “I think that’s a big part of what created our immediate bond. If you’re a horse girl, you just know.”

The actress also revealed that they had been eager to go on a “horse trip to Ireland together” once the world was “back to normal.” Meanwhile, after the show wrapped up its first season, Cuoco also gifted her co-star with an equestrian helmet.

Kaley Cuoco And Zosia Mamet Sometimes Live Together

When they went to work on the second season of The Flight Attendant, they had to do so in the midst of the pandemic, making it hard for Cuoco to keep her spirits up. Luckily for the actress, she had Mamet with her almost all the time since her co-star moved in with her.

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“I don’t know if I would’ve gotten through this without Zosia Mamet, who lived with me basically the entire time we were filming season two,” Cuoco revealed. “There were mornings where I was like, “I can’t get out of bed. I can’t go to work.” And she would get me out of bed, get me dressed, and put me in my car. Multiple times. She visited me on set on days off, when she didn’t have to be at work, because she knew I was having a hard time.”

Cuoco also admitted that she’s never really the type of person who enjoys sharing their space with other people. But in the case of Mamet, it just worked. “What’s funny is I’m not a roommate person. Even people know me and Karl [Cook, Cuoco’s ex-husband whom she split from in 2021] moved in very late together,” she explained. “I’m very funny about my space. Zosia was with me every day, and I don’t know what would’ve happened to me if she wasn’t, truthfully.”

At the same time, the bond between the co-stars even got stronger as they continued to work together. “It makes me very emotional because she’s become one of my closest friends,” Cuoco added. “I don’t know what I would’ve done [without her].”

At the moment, it seems too early to tell if HBO Max will renew The Flight Attendant for a third season. Whatever happens though, it’s safe to say that Cuoco and Mamet will remain besties. In fact, they’ve since gotten another set of matching tattoos together (the first one was in honor of the show). This time, it says “boop.”

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