After a Navy SEAL is found murdered in a sorority house, the NCIS team must determine if the motive pertained to one of his classified missions or collegiate foul play. Meanwhile, Pride's daughter, Laurel, pays the NCIS office a visit.

With New Orleans decorated for Halloween, the NCIS team investigates the murder of a Naval Staff Judge Advocate found in a cemetery dressed in a Victorian costume with vampiric puncture wounds on her neck. Meanwhile, the team debates what Halloween night activity and costumes would be best.