Dirty, Tattoo-Covered Rihanna Holds Machine Gun in Battleship Poster

She's known for her wild fashions, stepping out earlier this week in thigh-high leather boots and studded sorts, butRihanna's latest look might be her most surprising -- and shocking -- yet.

PHOTOS: Rihanna's crazies...le moments

Covered in dirt, rocking tattoos, and holding a machine gun, the usually glam singer looks super fierce in an Italian-language promotional poster for her upcoming movie debut in Battleship.

Rihanna, 23, plays a U.S. Navy officer in the action flick alongside Liam Neeson,Alexander Skaarsgard, Brooklyn Decker and Taylor Kitsch.

PHOTOS: Rihanna's hair th... the years

"She was great. She has a very strong part," the film's director, Peter Berg toldMTV News. "I was surprised no one had ever thought to hire Rihanna. I was a huge fan of her videos."

PHOTOS: Rihanna and Chris...antic past

He added, "Obviously she's sexy, but she had this real intensity. I'm like, 'Someone's going to get her.'"