NCIS Gibbs Bluff T-ShirtSpread the wisdom of Leroy Jethro Gibbs with this fun yet wise NCIS t shirt! The NCIS Gibbs Bluff T-Shirt is black. It features a portrait of Agent Gibbs, the leader of the Naval Criminal Investigative Service on TV's NCIS known as "Boss," with his quote, "The secret of a good bluff is not to bluff."