Rila is first mentioned by Falere when Commander Shepard meets her on Lesuss while investigating a distress signal. Falere tells the squad that Rila was dragged by Reaper forces into the monastery's Great Hall to be turned into a Banshee and begs the Commander to save her. However, when Shepard tells her about the bomb intended to destroy the monastery, Falere becomes angry and accuses Shepard of not trying to help people. She sets off by herself to find Rila.
After fighting their way to the Great Hall, Shepard finds Falere desperately trying to wake Rila, who appears to have fainted. Rila manages to regain consciousness, but she has begun to suffer the effects of indoctrination, and attacks Falere before being knocked out again. After Shepard holds off Reaper attackers from sabotaging the bomb, Rila is able to fight the indoctrination briefly and finds the bomb's detonator, insisting that Falere leave with Shepard while she stays behind and sets off the bomb. Falere struggles, but is dragged by Shepard to an elevator. Rila is attacked by several Banshees, one of which picks her up and mortally wounds her. In a final show of strength, Rila declares that the Ardat-Yakshi are not the Reapers' slaves and triggers the detonator.