Rebecca Chambers is an eighteen-year-old chemist who is a member of the Raccoon City S.T.A.R.S. She is 5'3" and very attractive. Her youth and femininity make her male teammates protective of her. Rebecca is a survivor of the Spencer mansion incident, her first mission with S.T.A.R.S. When Rebecca meets David at Barry's house, she learns that S.T.A.R.S. has been bribed or blackmailed by Umbrella, and when David asks her to accompany him to an Umbrella facility in Caliban Cove where he suspects similar activities as in Raccoon City, she agrees, eager to do her part. Unfortunately, as Barry's team plans, they are attacked by Umbrella forces led by members of S.T.A.R.S. Barry, Chris and Jill hide in Brad's cottage, planning to try to find more information, while Rebecca accompanies David to Caliban Cove.
After Rebecca and David join his team, Steve, John and Karen, the five S.T.A.R.S. set out for Caliban Cove, but they are forced to shore when their raft is overturned by monstrous creatures. In between taking refuge and battling Trisquads, zombie trained with guns, the team solves riddles left by Dr. Ammon, the Caliban Cove researcher that alerted Mr. Trent, the S.T.A.R.S.'s mysterious benefactor, to the situation at the facility. When Karen is infected during Ammon's tests, the team decides to infiltrate the lab in search of a cure; however, Dr. Griffith sends one of his slave doctors to separate the group and take Karen and Steve hostage while he releases the Ma7s, violent and unpredictable creatures, to kill David, Rebecca and John. After infecting Steve, Dr. Griffith sends him to shoot John and trap Rebecca and David in the airlock which he intends to flood. Dr. Griffith talks to Rebecca and David and is furious they do not understand the beauty of his "gift". As David loses all hope, Rebecca worries about Griffith releasing the virus on the world, and when she recalls the grenade that Karen carries for luck, David drops it into the door, killing Griffith and allowing Rebecca and David to swim to the surface where they are retrieved by the Philadelphia S.T.A.R.S. team that Barry contacted. Rebecca sleeps on the boat after she along with David and John are pulled out of the water.