When a Navy captain is found dead with an unusual costume hidden under his uniform, NCIS uncovers a secret society of real-life super heroes and must track down the villain.

Top-secret clearance from a Naval research laboratory is jeopardized when the murder of a Chief Petty Officer is connected to an international arms dealer. Meanwhile, Probationary Agent Ned Dorneget tries to butter up Gibbs in hopes of joining the team.