It was intended that Sulu's role be expanded in the second season, but Takei's role in "The Green Berets" (1968) as Captain Nim, a South Vietnamese Army officer alongside John Wayne's character, took him away from "Star Trek" filming and he only appeared in half the episodes of that season. Walter Koenig as Pavel Chekov substituted for him in the other episodes. When Takei returned, the two men had to share a dressing room and a single episode script. Takei admitted in an interview that he initially felt threatened by Koenig's presence, but later grew to be friends with him as the image of the officers sharing the ship's helm panel side-by-side became iconic.