Alexis White is a Fulcrum operative, part of the Fulcrum team which spends the episode trying to recover a data chip that was taken from Brad White's body which had information about the identity of the Human Intersect.
In the past, she was a CIA operative assigned to the Special Forces. She speaks English, French, Russian and German. Cole Barker was going to meet with Alexis and her team to obtain the playback device needed to watch the footage he had taken from White. This plan was most likely a Fulcrum trap, which would have ended with Fulcrum getting the chip back.
Sarah, Cole and Casey go to the meeting but are captured when Chuck, who is examining the real chip at the Buy More, accidentally sets off a homing device. When they are all in the custody of Alexis, Chuck covertly reveals to his team that its video of him on the chip, and the Fulcrum agents are after the identity of the Intersect.
The Fulcrum agents try to information by torturing members of Chuck's team which results in Chuck revealing that he's the Intersect, while Barker counters that he is the Intersect. Alexis White brings a syringe filled with poison very close to Chuck. Chuck, tied to a wheelchair, tries to move away but leans too far and hits his head and knocks himself out. Casey and the team break in to where Chuck is and corner the Fulcrum agents. Casey demands the leader to tell them about Fulcrum, but she injects herself with the poison in the syringe, committing suicide. Her last words are "Fulcrum wins."
During Chuck's flash on her, the files show Alexis performing several bloody interrogations on both men and women, suggesting that torture may be her particular specialty.
Alexis was briefly mentioned again by General Beckman before a review of the Intersect project by a military panel to counter claims by Daniel Shaw that Chuck was losing control due to the Intersect. Shaw flashed on Alexis's name, and although Chuck witnessed and recognized that Shaw had flashed, was unable to prove his allegation.