Jackson Farrell is a professional criminal on the run from the police for bank robberies on the West Coast. Possibly based in Honolulu or Los Angeles, he robs the Monarch Bank of $500,000 and flees to the South Pacific on his boat, the Sea Spray, to hide out on a deserted island from the authorities. Unfortunately, he runs into the survivors of the S.S. Minnow. Passing himself as a doctor, his cover is blown by their radio, and he holds them hostage in their huts, later passing them off as uneducated natives when the Indigo Mob searches the island for him. Gilligan in particular is of great annoyance to him. After Gilligan is the cause of his stolen money getting chopped up, Farrell tries to shoot him, but his gun malfunctions. He flees the island and eventually gets captured, possibly by the Coast Guard in tandem with the FBI. His later whereabouts are unknown, but it is very likely he was sent to prison.
- Jackson Farrell was played by television and voice actor Larry Storch.