Zarm, a spirit of war and conquest that was once the spirit of Earth tempts the planeteers with power and pits them against each other. Matee's "heart" power breaks him free of Zarm's control, allowing him to eventually save the planeteer's from Zarm's corruption. The planeteers realize that an iron fish ethos will do more harm than good, even if done with good intentions and summon Captain Planet to send Zarm back to his world.
Skumm has given 6 people nuclear triggers banking on their hate for one another to set off a nuclear war. Gaia shows the six people the effects of nuclear war on the area around them and what happens if they let their hate control their actions.
Gaia warns the planeteers of unsafe nuclear practices that threaten the Earth and what a world polluted with nuclear radiation would look like. Gi and Linka discuss the harmful properties of nuclear radiation on human bodies.