The Big Bang Theory star Simon Helberg has revealed documenting his personal life for a film is terrifying.

The US actor, best known for playing aerospace engineer Howard Wolowitz in the award-winning comedy, has written, directed and stars in We’ll Never Have Paris, a romantic comedy based on his real-life engagement to his wife, Jocelyn Towne.

Simon said: “The film is based on the story of our break-up and then our proposal that followed shortly after, both of which were epic intercontinental disasters.

“We are married now, and thought, ‘Let’s tell the story of our demise and relive that for years to come’. Why we did that, I’m still trying to work out. It’s really personal, it’s really scary. I feel freaked out knowing that this movie is going out into the world.”

Jocelyn Towne and Simon Helberg
Jocelyn Towne and Simon Helberg (Evan Agostini/Invision)

The 34-year-old actor said reliving the experience is not at all therapeutic.

“The ideal version is that it was cathartic, but I think it was a bit more masochistic probably in some ways, and twisted,” he explained.

“Watching it again with an audience helps. There’s a lot of gasping and smacking of the forehead or that kind of laughter where you would hear at a tragic crime scene that’s very inappropriate. That’s great.

“I know that means people are relating and I think that as long as people are relating in some way, even though it’s an embarrassing time and it’s a pretty poor light I’ve shown that guy in, I know that that’s good because it’s human and it’s flawed and that’s the way we are.”

The film, which premiered at the 2014 Edinburgh Film Festival, stars Melanie Lynskey as Simon’s wife Jocelyn.

“Me playing a version of myself was cool but we didn’t want to get into working our issues out on screen. We didn’t have a conversation about it but we knew we needed to cast somebody else (as Jocelyn). We would have needed a lot of therapy for years to come,” he said.

Star Trek actor Zachary Quinto also makes an appearance as Quinn’s sarong-wearing friend Jameson.

Simon said: “I was just so excited because I had never seen him do anything like this. You don’t really get to see him play this kind of eccentric, bohemian guy in a comedy and I thought that would be exciting.

“And to have him wear a sarong, I think that’s something the world is waiting for. You can’t put any man in a sarong and have him water the garden, but Zach was ready to do it.”

We’ll Never Have Paris is in cinemas now.