Bradley Cooper may have just revealed a major plot point from upcoming Marvel film, Guardians of the Galaxy 2.

During an interview on the press tour for his film Burnt with co-star Sienna Miller, Cooper either completely forgot the plot from the first movie or confused it with the yet-to-be-released sequel.

Fans of the film know that the father of Peter Quill (played by Chris Pratt) will be revealed in the upcoming film, but in an interview with MTV, it sounds like Cooper may have just revealed who it is.

“Josh Brolin’s the villain, no? Or he’s the main villain, no?

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“He was in the first one, he played whatshisname’s dad. You know who I’m talking about?

“The Dark-Lord… the main guy.”

Clearly confused and on to the fact a spoiler may have just been revealed, the interviewer told Cooper that particular piece of information had not come to light in the original film.

“But that’s not his Dad is it?”, she asked an increasingly defensive Cooper.

“I thought it was his Dad… Maybe I misread it,” he said.

“You just leaked a Marvel script, Bradley,” chimed in Sienna Miller, who tried to move the conversation on to another topic.

In an attempt to lighten the mood, Bradley then hypothesised maybe he’d seen a completely different film altogether.

“Maybe that was the same movie Rocky was in, just hitting everybody,” he added.

“Brolin and Rocky go around hitting on aliens. You know, Guardians of the Galaxy.”

Whether Cooper just let a major plot line slip or simply didn’t remember a crucial detail from a film he was in, all will be revealed when the sequel comes out in 2017.

Watch the awkward clip here: