Second and Final Confrontation Between Gibbs and Mishnev is a confrontation that occurred in January 2015 in which NCIS Special Agent Leroy Jethro Gibbs confronted terrorist Sergei Mishnev a few hours after the Murder of Diane Sterling. Although Gibbs came close to strangling Mishnev, he was later knocked unconscious by one of Mishnev's henchmen, allowing Mishnev to escape.