Gecko was once a regular reptile, who gained intelligence when he drank a sample of Curt Connors' DNA which leaked into the sewer. Gecko and his companions Gila and Monitor also inherited The Lizard's superhuman strength. They kidnapped Connors, claiming that he was their 'father', and planned to take over the world and populate it with intelligent reptiles like them. When Mary Jane Watson, Margaret Connors and Debra Whitman arrived, Gecko was returned to normal along with the other lizards.
- The character was voiced by Roger Kern in Spider-Man: The Animated Series.