Robert Pattinson was threatened he'd be fired if he didn't smile in 'Twilight', and he was forced to read through the novels and highlight his characters expressions to help him keep his job.
The 31-year-old actor portrayed Edward Cullen in the fantasy franchise, which was released in 2008, and the star has revealed he took the role far too seriously to a point the production team were close to sacking him and casting another star in his place.
Speaking about his breakout role, which saw him star alongside his former girlfriend Kristen Stewart, to Howard Stern on his Sirius XM radio show, he said: "If you're going into a relationship with someone, the way to make it really intense is if you can barely talk to each other, you can barely touch each other, it's incredibly serious all the time.
"That's what teenage relationships are. But everyone kind of wanted it to be, like, 'No, they should just be, like, happy and having fun. That's what people want.'
"I thought I was pretty safe. They [his agents] flew up and were like, 'You have to do the opposite of what you're doing now or you're going to get fired today.'"
The dark-haired heartthrob - who is currently dating FKA Twigs - was given a "compromise" and was forced to read through author Stephenie Meyer's novels, which the franchise is based on, and highlight in different colours every time the character smiled or frowned to help him with his role and keep the job.
Robert continued: "I was probably going a little too miserable, so there was some kind of compromise made."
And the London-born star has made it known he took Valium to help him calm his nerves before he went into his first audition for the movie, but the medication only made him sleepy.
He explained: "I couldn't barely keep my eyes open when I talked to the producers."