Quick recap
Dexter carries the guilt for Rita's death and raises Harrison alone. While killing Boyd Fowler, he finds Lumen Pierce, held captive in the house, who saw everything. Lumen was tortured by a group of men and asks for help hunting them. Dexter agrees, partly to make up for failing Rita. The trail leads to motivational speaker Jordan Chase, the group's leader. Stan Liddy, a dirty cop Quinn hired, photographs Dexter and captures him; Dexter kills him. Chase kidnaps Lumen, and Dexter subdues him and lets her kill him. Debra catches them behind plastic sheeting, can't see their faces and lets them go. Her urge to kill gone, Lumen leaves.
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