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Rihanna dove headfirst into her movie career, choosing the big-budget summer action flick Battleship as her first cinematic project. Judging from the training necessary for the part, her next film venture should be a piece of cake by comparison.

VIDEO: Rihanna Admits to Nerves While Shooting First Film

Rihanna told Chris Jacobs that director Peter Berg's technique for getting the most natural performance was to not give her the time to over think the job.

"Right away I was saying lines, which I never had [ahead of time]," said Rihanna, who felt the method did a good job of getting her out of her head. "And then I'm training with weapons in [Pearl Harbor] to go and shoot a weapons scene."

Rihanna revealed that with her already full schedule she had to cram most of her military training into the time when she was on set.

"I didn't have time to rehearse with the crew and the cast but after I worked with the soldier it was really intense -- a lot of yelling at me, a lot of breaking everything I had grown accustomed to as Rihanna," said Rihanna.

RELATED: Exploding Action in the New Battleship Trailer

Battleship, which is based on the classic naval battle board game by Hasbro, also stars Oscar-nominated actor Liam Neeson, Just Go with It star Brooklyn Decker and True Blood star Alexander Skarsgard.

The movie hits theaters May 18.