Striving to bring some normalcy back into his shattered life, Dexter figures the answer lies in finding a new serial killer to bring down, but his quest gets thrown off course when his troubled new acquaintance, Lumen, requires his help to find one of her attackers. Meanwhile, Batista uncovers a revealing new lead in the Santa Muerte homicides, and Quinn gets a tip about Dexter from Liddy, but is not sure he can trust his source.