Symphony Clean Bandit & Zara Larsson
The 'Cheers' singer talks about her rigorous training schedule.
Rihanna has admitted that the acting classes she took before making 'Battleships' were tougher than your average.
"One man drilled me, yelled at me, cursed me out, made me do push-ups," RiRi said.
"My best friend was there and I told her, 'I'm about to do acting class. You're gonna want to kill this man but please, just stay in the other room.'
"She would come in and just look around and be like, 'Did he just say 'F you' to her?'"
Rihanna's first big movie role sees her playing a tough FBI agent who joins the navy in an alien-fighting mission, thus the intense army-style sessions.
The workouts included weightlifting, running and swimming while being shouted and sworn at by the boot camp officer.
"It got you really in the mentality," she told movie site Fandango.
"That's the stuff that they go through, it's not a walk in the park...
"I was so scared, I just looked at him like, 'I swear I'll get it right, I'll be good!'"
Battleship is set for release on 18th May 2012.