Kaley Cuoco & Johnny Galecki Broke Up In Real Life Mere Weeks Before Their TBBT Characters Did

We may receive a commission on purchases made from links.

Some of the greatest Hollywood love stories started on set, but usually off camera. But, fans of "The Big Bang Theory" can actually see the moment Kaley Cuoco and Johnny Galecki first fell for one another. Jessica Radloff interviewed the pair for her book, "The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series." Cuoco and Galecki discussed their relationship and how filming a dream sequence in the Season 1 episode "The Nerdvana Annihilation" kicked things off. In the scene, Leonard (Galecki) imagines him and Penny (Cuoco) kissing in an elevator shaft, and, according to Cuoco (via Vanity Fair), "I think we fell a little in love in that elevator shaft." Galecki backed her up, "I think that was a massive turning point [in our relationship]." The couple started dating in real life, and their characters soon followed suit. Sadly, Cuoco and Galecki didn't last, and less than two months after they broke up, the show's writers decided to have their characters call it quits as well.

Cuoco and Galecki secretly dated for two years, with Cuoco revealing it to CBS Watch Magazine (via HuffPost), saying, "It was a wonderful relationship but we never spoke a word about it and never went anywhere together." Galecki elaborated in Radloff's book, "It was a lot of fun to teach one another different things, but then when I came to wanting different things, that made things more complicated." 

The two chose to keep their breakup a secret from their coworkers, which led to an awkward moment on set. Talking about filming the breakup on "The Official Big Bang Theory Podcast,"  director Anthony Rich explained that as they filmed a scene together, Cuoco "let her guard down. And I think, at that particular moment, she started sobbing."

While Kaley Cuoco and Johnny Galecki's characters on "The Big Bang Theory" ended back up together and got married, the actors never got back together. After a few other relationships, including two marriages, Cuoco started seeing "Ozark" star Tom Pelphrey in 2022. While Cuoco initially didn't want to have children, she and Pelphrey welcomed their daughter into the world in 2023. Cuoco and Pelphrey became engaged in 2024, and, in June 2026, Cuoco took to Instagram to announce that the couple had another girl on the way, writing, "@tommypelphrey girl dad for life."

Like his former co-star and romantic partner, Galecki has also had a few relationships since he and Cuoco broke up. In 2018, Galecki started dating model Alaina Meyer, and the two had a child together before splitting up in 2020. Fans of the actor were shocked when Galecki revealed that he was seeing someone in an Instagram post in 2023. A year later, Galecki revealed that the mysterious woman was named Morgan, and that they had gotten married and were expecting their first child together. The couple has never revealed how they met or exactly when they got married, choosing to keep their lives private. 

As for Galecki and Cuoco, there are no hard feelings. Galecki attended Cuoco's 2014 wedding to Ryan Sweeting, and Cuoco spoke about their relationship to Cosmopolitan (via Today) saying, "It took a minute, a bit of awkwardness. By the grace of God, we became best buddies and moved on in such an elegant way." While on "Watch What Happens Live" in February 2026, Cuoco revealed that, while there isn't a "Big Bang Theory" group chat between all of the actors, there is a chat "with me and Johnny."