Adam-12 - Season 5 Episode 3 : Airdrop 1975

Malloy and Reed are patrolling the outskirts of Los Angeles when a girl on horseback alerts them to a small plane that landed in a secluded area. When the officers investigate, they see a pickup truck fleeing and the plane trying to take off; though they stop the plane, they have no proof the pilot did anything. Malloy and Reed later learn from the DEA that a Mexican cartel is behind the landings, with the pilot instructed to play dumb if caught. The officers find the pilot and trace the pickup truck's location, and the truck is followed to the landing site, where the smuggler and the pilot are arrested.