The Ghost was a Russian espionage agent who turned up on the island trying to scare the Castaways off to procure the off-shore oil rights. His real name was unknown, but he floated through the hut area moaning and sticking Mr. Howell's practice polo pony in a tree. Upon realizing they could not leave, he arranged to leave them a boat, but the Professor deduced he might be trying to kill them. The Ghost eventually fled the island upon thinking he was haunted by the Castaways he supposedly killed.
- The Ghost was played by actor Richard Kiel, best known as Jaws in the "James Bond" franchise. His speaking part through the episode was possibly by Charles Maxwell, but this is unconfirmed.