Callen races against an adversary to locate a woman who knows the whereabouts of a forgotten fortune earmarked to fund a new war in the Middle East - and also holds the key to his unknown past.
After Callen's cover is blown and compromises the unit, the NCIS team races to find out who is behind the security breach.
After a sailor is killed during a street race, the team determines that his car had been sabotaged and contained confidential equipment. Meanwhile, Callen is forced to take traffic school.
The murder of a recently released convict forces Callen to go undercover solo as an old alias, while Sam and the LA team track him from a distance.
Following the murder of a Russian woman, the NCIS team uncovers evidence that answers who and why Callen was shot six months ago.
Newly located in a Los Angeles mission, the NCIS Office of Special Projects (OSP) welcomes Callen back to the team and races to solve a kidnapping case.
G. Callen career is an experienced NCIS agent whose penchant for undercover work is legendary. Fittingly, he was introduced during the NCIS episode "Legend."
His assignments have included stints in Serbia and Russia. Callen is described as 'a chameleon who transforms himself into whomever he needs to be to infiltrate the criminal underworld'.
Twice, over the course of his career, Cullen's life was saved by Leroy Jethro Gibbs, once in Serbia and once in Russia.