First aired
April 9, 2019.
Written by
Directed by
Previous episode
Perennial is the 19th episode of NCIS Season 16 and also the 373rd episode of the entire NCIS series.


Following an active shooter lockdown at a naval hospital, the NCIS team searches for a suspect who fled the scene with Sloane also investigating after she discovers that someone from her past was inside the hospital and as such, is a key witness in the case.

Major Events

  • Gibbs admits to McGee that he burned Rule 10.
  • Jacqueline Sloane is revealed to have had a daughter whom she promptly put up for adoption, despite genuinely loving her.
  • Bishop kept a dying plant for Ziva, and resumed payment.


Series Regulars

Name Portrayed by Role
Leroy Jethro Gibbs Mark Harmon Special Agent in charge of the NCIS Major Case Response Team.
Timothy McGee Sean Murray Senior Special Agent and second-in command of the NCIS Major Case Response Team.
Nicholas Torres Wilmer Valderrama Special Agent for the NCIS Major Case Response Team.
Eleanor Bishop Emily Wickersham Special Agent for the NCIS Major Case Response Team.
Jacqueline Sloane Maria Bello NCIS Forensic Psychologist.
James Palmer Brian Dietzen Chief Medical Examiner for the Major Case Response Team.
Kasie Hines Diona Reasonover NCIS Forensic Specialist; Abby's successor.
Leon Vance Rocky Carroll Director of NCIS
Donald Mallard David McCallum NCIS Historian. Despite being credited, McCallum doesn't appear in this episode.

Other Cast

Name Portrayed by Role
Faith Tolliver Kate Hamilton NCIS Forensic Psychologist Jacqueline Sloane's daughter.
Noah Sykes Brian McNamara Evan Sykes's father.
Dale Moseby Sam Daly Virginia State Police Officer.
Odette Malone Elayn J. Taylor
Eugene Pierce Merrick McCartha Doctor.
Unnamed MPD Cop Brian Oblak
Veronica Crawford Jennifer Carta Navy Captain.
Unnamed Young Man Kyle Grossmeyer
Unnamed Nurse (Perennial) Charlotte Evelyn Williams
Unnamed Doctor Roopashree Jeevaji
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