When "Guardians of the Galaxy" director James Gunn told MTV News on the red carpet for "Thor: The Dark World" that Rocket Raccoon voice actor Bradley Cooper sits in the recording studio "until his voice is sore and his eyes are bloodshot, and he's bleeding from his nose and ears," we didn't know whether to be excited for the upcoming Marvel move or worried for the Oscar nominee.

It turns out that Cooper's doing all right, and at the press junket for "American Hustle," he only had good things to say about working with Gunn, and he confirmed Gunn's work ethic and his insistence on getting the talking raccoon that he wants.

"It's been great. The great thing about [Gunn] is that I tried to set the ground rules early. I said, 'Look, you don't have to sugar-coat anything. Just tell me exactly what you want,' " Cooper shared with MTV News' Josh Horowitz. "I think he was basically going like, 'Did you think I would do anything else?' "

At the event for the "Thor" sequel, Gunn also mentioned that the CGI raccoon would be the heart of Marvel's upcoming sci-fi superhero movie, but Cooper had a slightly different take on the film's emotional center. The actor thinks it belongs to Chris Pratt and his character, Star-Lord, calling the half-alien gunslinger "Han Solo and Luke combined."

But together, Rocket and Star-Lord balance each other out in a way that recalls a classic movie pairing. "I think Rocket is dynamic," Cooper added. "He's the sort of Joe Pesci in 'Goodfellas' guy. You need Henry Hill."

For as many good things as Cooper had to say about the character and working with Gunn, a recent coincidental discovery about Rocket Raccoon's origin suggested to the actor that his connection to the character goes even deeper than that. On the set of Cameron Crowe's new movie, the writer/director played music, as he usually does, for the cast during scenes. One of the songs was the Beatles' "Rocky Raccoon," a song that Cooper loves.

"This is actually kind of crazy. Talk about a weird thing. 'Rocky Raccoon' is one of my favorite songs," Cooper revealed. "For some reason, it just f---ing kills me. It's pathetic; it destroys me," he admitted. "When the role of Rocket Raccoon came upon us, I was talking to James Gunn and I said, 'I'm doing this movie now, and we're always tripping on Rocky Raccoon. Isn't it weird that I'm playing Rocket Raccoon?' He told me that was the inspiration for the character, that song. I don't know if that's the truth, but it's what he said, which if that's the truth, it's kind of insane."

In case you were wondering, it is true.

"Guardians of the Galaxy" opens in theaters on August 1, 2014.