"Internal Affairs," the 14th episode of NCIS Season 5, aired on April 22, 2008, and resolves the "La Grenouille" storyline by investigating the death of arms dealer René Benoit. The episode features the debut of Rocky Carroll as Leon Vance, while the team uncovers CIA involvement in the case despite being under FBI interrogation. For more details, visit NCIS Database . "NCIS" Internal Affairs (TV Episode 2008) - IMDb