Things grow more tense after Lindsay is forced to stay in the Pi Epsilon Delta following a fire and after making up with Finn, Sarah discovers that Trina Goodwin is not her true mother and that Trina actually killed their birth mother after a failed ritual. The Alpha Nus had believed her to be the One, which had been proven to be false after the Knife of Truth refused to cut her, as it will only cut the flesh of the One. Sarah also learns that the Alpha Nus are willing to kill her if they can't have her, which prompts her to try to rescue her sister from their clutches. She initially seems to be successful, as Lindsay appears to want to leave the group, but this is soon revealed to be a trap to capture Sarah and force her into sacrificing herself willingly. However everyone is shocked when a struggle reveals that the true One is actually Lindsay rather than Sarah, as the Knife of Truth ends up nicking her throat. They also find that the Knife can cut through anything if it has the blood of the One on it.