The Body-Swapper is the eleventh episode of the second season of the animated series, Martin Mystery. It was originally released on October 3, 2004.
M.O.M. and Diana decide to break Martin of his habit of always borrowing their stuff. But that's soon overshadowed by the problems at the Center's base in the Canadian Arctic where Martin has the choice of co-operating with his old rival Marvin (who blames Martin for his transfer to the frozen tundra) or becoming a host for the body-snatching creature that's been accidentally unearthed and is growing stronger with every host it takes.
When a distress call from a group of agents at the Center's base in the Canadian Arctic, Martin, Diana and Java travel there to discover that a body snatching creature has escape from it frozen prison and began to taking over anybody it come into contact and with every host it takes, it become stronger.
Tired of Martin "borrowing" her stuff, Diana "borrowed" the Center's new gadget, the Neurological Interrupter, plus also used it to consistently shock Martin while on their mission.
- Hosts Diana, Marvin & Martin (formerly)
- Diana (Only as a minor one. Mostly because of the The Neurological Interrupter)
- This episode brings back Marvin, who is revealed that after the event of "The Third Eye", Marvin's punishment was that he was stationed in the North Pole.
- The episode pays several homages to John Carpenter's film, The Thing, taking place in the Arctic, the creature sometimes failing to completely transform, and it mimicking a dog.
- This was the last episode that uses the body and eye scans with a female voice saying, "Martin Mystery, clear.", "Diana Lombard, clear." & "Java the Caveman, clear." Then, with Billy saying his quote, "Hey, guys." with the trio saying, "Hey, Billy." back to him and finally, using the elevator to M.O.M.'s office, since it happened when they entered the Center in various places and objects whenever they get to, in these episodes in two seasons.
- This episode is recognized that one of the Worst episodes of the series, due to it portraying Diana as a minor antagonist throughout the episode do to her stealing the Neurological Interrupter and using it on Martin.