The story revolves around a space station inhabited by independent robot animals. The station reappears on a collision course towards Earth, prompting humanity to send squads to stop it. However, all but one of the robots, Evo, get lost during the rescue mission. As Evo, the player must solve 35 levels to save the planet.
The game's unique feature is that Evo can control any robot animal he meets. This ability becomes essential due to Evo's rapidly decreasing life energy when outside a host. Each animal has distinct abilities used to overcome puzzles in each level. The goals vary from destroying machines to guiding sheep to their pens.