ET Exclusive: On the 'Battleship' with Rihanna

Rihanna takes on her first dramatic role in the summer blockbuster Battleship, and our own Mark Steines is exclusively with the Grammy winner on the USS Missouri in Pearl Harbor, HI.

"I got to shoot some really serious, powerful weapons, which is really, really fun," says the singer, decked out head-to-toe in camouflage and fake tattoos. "We wanted a bunch of tattoos just to dirty me up a little bit -- and, of course, no makeup."

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Based on Hasbro's classic naval combat game, the epic action-adventure unfolds across the seas, in the skies and over land as our planet fights for survival against an out-of-this-world, superior force. Rihanna plays Lt. Raikes, a crewmate and a weapons specialist on the USS John Paul Jones. She faces the enemy alongside Taylor Kitsch, Alexander Skarsgård, Brooklyn Decker and Liam Neeson.

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"She's this badass weapons officer; she knows everything about weapons, not only hers, but all the weapons on board," explains Rihanna, who went through some basic training exercises like a new recruit to prepare for the film. "It really got me into the emotion of the character. … She's a fighter. She's a killer. She's not afraid of anything. She likes a challenge because she can handle it."

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The role requires a lot of ocean swimming and "really physical" acting amid chaos and explosions. In between skirmishes on land, sea and in the air, is there any romance on deck for Lt. Raikes?

"Not at all -- she could care less about boys," replies Rihanna. "I'm one of the boys."

Clearly this isn't The Love Boat.

Battleship blasts into theaters summer 2012.