In the film, she is a rogue CIA agent who is secretly an underling of Kananga, aka "Mr. Big", who sends her to kill 007. When arriving at a hotel in San Monique, Bond is surprised to learn that "Mrs. Bond" has already booked into the suite. She casually mentions that Bond is only her second assignment; her first was being previously paired with Baines, suggesting that she is incompetent at her job.
After spending the night together, Bond and Rosie head off deep-sea fishing, while they check over the rest of the island. Bond hires Quarrel Junior. While aboard the his boat, Rosie finds a secret compartment with radio transmitters and weapons and jumps to the conclusion that Quarrel is a villain. When she spots him coming up from behind Bond with a rope, she holds the fisherman at gunpoint. Bond however clears up the situation; revealing that the two are acquainted.
The pair arriving near the alleged location of Baines' death. After a picnic where they make love, Bond confronts Rosie, and learns that she is actually in the employ of Kananga and she was to lure Bond to a trap where he would be killed. When Bond threatened to kill her if she didn't come clean, Rosie called his bluff and runs away, being killed only moments later by Kananga’s scarecrows.
Behind the scenes
Rosie Carver is Bond's first on-screen black love interest. Her character was initially written as a white woman (and the lead Bond girl, Solitaire, as black) before the producers made the switch. During filming, the producers actually thought about sparing Rosie, but ultimately they went ahead with the original plan and killed her off.