Inside 'The Flight Attendant' Kaley Cuoco and Zosia Mamet's Close Friendship

"The Flight Attendant" stars Kaley Cuoco and Zosia Mamet might not be lovers, but they are a match made in heaven. They even got matching tattoos to honor their relationship.

Making new friends is not always easy and usually takes time, but "The Big Bang Theory" alum Kaley Cuoco and "Mad Men" star Zosia Mamet clicked right away.

They met during a chemistry read for HBO Max's "The Flight Attendant" in late-2019 – the critically-acclaimed TV series nominated for Golden Globes, Emmys, and Screen Actors Guild Awards.

Mamet and Cuoco had so much fun together that day (they wouldn't stop improvising and playing with each other) that everyone was convinced they were best friends. However, it was the first time they had met.

The actresses got closer while working on "The Flight Attendant" and eventually became best friends. In October 2020, they honored their friendship by getting matching tattoos of paper airplanes – a nod to their TV series.

In April 2022, Kaley Cuoco and Zosia Mamet's tattoos made headlines again after getting the word "boop" inked on their inner biceps. Cuoco talked about the body art's backstory during an interview with "Good Morning America," linked to her and Mamet's first meeting.

Cuoco affectionally poked Mamet's nose with her index finger during their chemistry read and said, "boop." Mamet swatted her hand away but then did the same to Cuoco.

We're basically a married couple.

They did it so many times that it became their thing. Cuoco even registered Mamet in her phone under "boop," so they decided to get the word tattooed because they are "insane." Cuoco said:

"We are just so close, and this year was really heavy, and we just wanted to mark it because she really got me through a lot."

Cuoco is not the only one saying beautiful things about her best friend. Mamet described her "The Flight Attendant" co-star as an epic human being, adding that they got "almost annoyingly" close. Mamet revealed:

"I'm literally at her house right now. I live in New York, but I'm staying with her while we're out doing press, so we're basically a married couple."

Mamet also praised Cuoco for her impressive work as an actress and executive producer on their show. She admitted that the "8 Simple Rules" star was an "exceptional" captain who watched out for everyone.

After saying she had never seen someone multitask how Cuoco does, Mamet revealed she has a lot of fun working with Cuoco and Australian actor Deniz Akdeniz on "The Flight Attendant."

Depending on the occasion, the three actors need to be told to wrap it up and reminded that they are supposed to make a TV show.

"The Flight Attendant" season 2 premiered on April 21, 2022, to positive reviews. Zosia Mamet said the writers did a great job at going bigger and louder with the thriller aspect of the show while also cracking open each character.

Kaley Cuoco described the show's second season as a whole new adventure for Cassie, her character. Cassie's alcoholism is a driving force in the first season, but being sober is a significant aspect of the second. Way to go!