Gex is a platformer game where you control a gecko character named Gex as he tries to defeat the evil Rez by collecting remotes. The story takes place inside a television set, where Gex must navigate through various worlds, each accessible by opening a door within the TV. Gex has a range of skills at his disposal, including jumping, fire, close-range attack, suction cups for climbing walls, and a tongue to grab power-ups.
Gameplay revolves around using these abilities to traverse through levels, collect pickups and power-ups, while avoiding or killing TVs that get in his way. The game's tone is light-hearted, with Gex delivering witty one-liners as he progresses through the game.