Mayim Bialik, who plays Amy Farrah Fowler on CBS comedy series “The Big Bang Theory,” has confessed that "The Opening Night Excitation" episode, which saw her character finally have sex with her boyfriend Sheldon (Jim Parsons), surprised her just as much as it surprised the audience.

The Episode 11 of “The Big Bang Theory” Season 9 saw Sheldon (Jim Parsons) giving up on the new "Star Wars" film's premiere night tickets to spend time with Amy on her birthday. He decided to get physically intimate with her as his birthday present. This was a huge milestone moment for the couple after five years of on and off dating.

“I was honestly shocked! We had just gotten back together, and Jim and I had both settled into a very comfortable place with Amy and Sheldon having a non-sexual relationship. I guess the writers disagreed,” she said in an interview with CBS.

The actress, who has a real doctorate degree, added that the scene was much more tender and sweet than anything she imagined.

When asked if their sex scene should be considered as “makeup sex," she said that sex had nothing to do with their recent reunion. She explained that Sheldon’s mind does not work that way, adding "'Star Wars’ premiere. Amy's birthday. Special thing. Coitus” that's how his brain.

Amy broke up with Sheldon in the season finale of "The Big Bang Theory" Season 8, and in Episode 10 of the current season, Sheldon realised Amy's importance in his life, and they became a couple again.

Talking about what future holds for the two characters, Mayim feels that Sheldon and Amy would probably go back to doing all those things they did before the break-up.

“I don't think that every episode will be about a monumental relationship move, and I'm grateful for that. Our show tends to be about the day-to-day lives of these unusual people rather than monumental events in their relationships. And we like it that way,” she said.

“The Big Bang Theory” Season 9 will return with Episode 12 on Jan. 07. According to spoilers, Sheldon and Amy will be shown skyping in the new episode, as the latter is attending a neurobiology conference.

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