She and her co-stars Taylor Kitsch and Brooklyn Decker arrived at the premiere on a white navy boat with director Peter Berg (Hancock) and walked down a red carpet guarded by members of the Australian Navy.
The film is inspired by the Hasbro game Battleship, but Berg said he added the aliens element to it after watching a Stephen Hawking documentary, warning people about communicating with aliens, in case one day they decide to respond.
Berg said Rihanna came to read for lots of different roles but she fitted this "badass urban girl" part perfectly.
"The navy have a lot of women in there and I was looking for somebody that ... we hadn't seen before in film, and I believed kind of had swagger, and could kick ass, and look at her - she's got it," he said.
Decker broke out singing "oh na na, what's my name" when asked if she was a Rihanna fan, adding that they both had fun doing the gun and fight training.
"The fact that we bring two really empowered women to a movie that typically doesn't show strong, empowered women, is really special for us," Decker said.
Rihanna found their appreciation for the navy only grew after going through all that preparation.
"Definitely training for that film and wearing the uniform everyday on set," Rihanna said.
"I have only respect for them. They're real life heroes ... These guys are putting their lives on the line for their country."
Especially when aliens come to destroy humanity?
"Especially," she said.
Check out the Battleship trailer:
- AAP
