Gaia, the spirit of the planet, assembles a diverse team of "planeteers," who are able to combine their powers to summon an elemental warrior that takes on the appearance of superhero Captain Planet. He works with the planeteers to defend Earth from pollution caused by criminals and villains. As the show's theme song says, Captain Planet is "gonna take pollution down to zero" by defeating the villains, who include the likes of Hoggish Greedly, Dr. Blight and Looten Plunder. The animated series was co-created by media mogul Ted Turner, a noted environmentalist.

Verminous Skumm unleashes a swarm of hungry weevils upon a small town.

Aliens pit the Planeteers and the eco-villains against each other in a high-stakes game show to determine the fate of Captain Planet.

When the Planeteers investigate a string of bat attacks in New Mexico, they discover Looten Plunder's nephew, Robin, staged the attacks to build publicity for his upcoming movie, and must put an end to Robin's fearmongering.

The tables turn on the Planeteers when Hoggish Greedly secures a legal permit from the Army Corps of Engineers to build over precious wetlands and the authorities arrest Captain Planet; the team must stop Greedly while being hunted as fugitives.