Naval Criminal Investigative Service Special Agent Leroy Jethro Gibbs leads a group of colorful personalities in investigating crimes - ranging from murder and espionage to terrorism - that have evidence connected to Navy and Marine Corps personnel. The team includes MIT graduate Timothy McGee; Ellie Bishop, who specializes in international threat assessment; charismatic and unpredictable Nick Torres; and forensic psychologist Jack Sloane. Dr. Donald "Ducky" Mallard brings his vast experience in forensics into play to help solve cases.