- "I was just talking to Mitch, and he said that Galt and a couple of the deputies were... a little hard on the guy."
- ―Deputy Lester to Sheriff Will Teasle. [src]
Lester was first seen entering the Hope, Washington police station with some mail. He was looking down at the letters, and because of this, failed to notice half-crazed Vietnam War green beret veteran John Rambo running out of the police station with his survival knife. Rambo slid onto the ground and kicked Lester's feet out from underneath him. Lester scrambled to get up and Rambo elbowed him in the face, breaking his nose instantly. Lester's hands flew to his nose in pain.
Later on in the film, after the failed manhunt ambush, Lester revealed that Mitch told him that several of Will Teasle's deputies, especially Art Galt, had abused Rambo that caused him to snap in the first place, prompting State Police Captain Dave Kern to angrily declare the deputies as a bunch of 'assholes' for their cruel actions. Despite this, Teasle doesn't care about this, as he is still angry at Rambo for the death of Galt. Despite injuries sustained at Rambo's hands, Lester still did what was right and recognized that Rambo was not entirely to blame, making him one of the only decent deputies in the film.
Later on, Lester was at the scene of the gas station that Rambo lit on fire and caused to explode. Lester called Teasle on his two-way radio and told Teasle that they found no body, and to get out while he still could. Lester then screamed for everybody to get back from the flames.