Big Bang Theory actor had to call mum following first day on set after 'accidentally masturbating' during scene

Beloved The Big Bang Theory star Melissa Rauch has opened up about her embarrassing 'masturbation' moment on her first day on set.

The actor, 44, famously played Bernadette Rostenkowski on the popular sitcom, which aired from 2007 to 2019.

First introduced in season three as Penny’s (Kaley Cuoco) coworker at the Cheesecake Factory, she soon became Howard Wolowitz’s (Simon Helberg) love interest and eventual wife.

While Melissa's character was introduced to The Big Bang Theory viewers pretty seamlessly, something very different happened on set. Watch below:

"The first episode of the season I had a little...incident," she told Conan in 2013.

"We were shooting a scene and I'm in a hotel room bed and in my own personal life, whenever I get under covers, I'm always really cold.

"So I just tend to pull the covers up really high and just leave my head out and then I kind of like warm up my hands like I'm a boy scout starting a fire with sticks or something.

"So I'm under the covers and it's really cold on set, because they keep it cold and I'm under there and we're shooting the scene and - out of habit - I'm doing this (rubbing hands together) under the covers.

Melissa Rauch was introduced as Bernadette in The Big Bang Theory in season three (CBS)

"We shot the whole scene, there's a studio audience.

"And after the scene was over, our director and producer came over to me and they were like, 'We need to see your hands in the next take - it looked like you were having way too much fun with yourself under the covers'.

"Then after the show, we were we take our bows and I was talking to some people in the audience and this little boy said to me, 'Did you shoot that scene again with your hands out because it looked weird? Because my dad said it looked real weird.'"

On calling her mum after the show to tell her how the first day went, the actor said 'she was mortified'.

Melissa's mum couldn't believe it (YouTube/Team Coco/TBS)

"She's like, 'I hope people understand that you weren't really doing that, that's disgusting!'" Melissa added.

"'People have been fired from that, people have lost their careers for doing that in movie theatres!' She's so upset about it.

"So now every week I just keep on saying, 'Uh, something else happened at work...'

"And she's like, 'Stop doing that! You did it again? It's enough, keep your hands to yourself!"

Despite the initial hiccup, the Bernadette character became a staple of the show and remained with the cast until the last episode.