Lillian (Lilly) Loomis is the twin sister of Billy Loomis. His badass other half, who he'll do anything for can't get caught in the crossfire of what her brother has planned. But that all comes crashing down when she ends up dating his best friend, Stu Macher. Will she help her brother and get revenge for their mother's abandonment or will she betray him and finally put an end to their killing spree?