'Insurgent' Star Jai Courtney Has a 'Tumultuous Relationship' With Theo James

They have their good days and their bad days.

ET’s Brooke Anderson sat down with the stars of the latest installment of the Divergent Series: Insurgent, including the film's bad-boy breakout star Jai Courtney.

Courtney's clearing the air about a controversial tweet he posted from IMDB's Twitter handle during an Insurgent Q&A on Tuesday. When one user asked what Jai thought of Shailene Woodley and Theo James together, Courtney responded, "If I can't have Theo, no one can."

"It's not a joke I really meant that," Courtney told ET. "If I can't have Theo, no one can -- and sometimes it means that we come to blows. It's tumultuous. It's up and down like any rich, full relationship -- you can't have the good without the bad."

WATCH: 'Insurgent' Star Shailene Woodley on Social Media and Staying in Shape

"We're having a good day," Courtney said of the bromance. "You gotta enjoy these days when they come around, because you never know. Something could happen at lunch. He could say something in an interview that I hear about at some point and things could take a turn for the worst."

Another Insurgent star who's had run-ins with Jai? Shailene Woodley!

"I accidentally head-butted her [while filming] which I'm sure wasn't pleasant and I felt terrible," said Courtney. "Tough as she is, didn't bat an eyelid."

Of course she didn't. Because Shailene is tough as nails.

Check out this video for more set secrets from the cast of Insurgent.

Insurgent hits theaters May 20.