Synopsis: The Mercenaries are hired to stop a Mafia hitman known as the Leopard. When the Leopard's men attack, the Mercenaries kill them in self-defense, but are arrested anyway, only to end up in a cell next to the Leopard himself. When they rescue the Leopard from a fire in the jail, he offers them an opportunity to work for him as assassins. They turn against him, and battle ensues at the foot of an active volcano.
Synopsis: As the Mercenaries approach Mars to destroy the missiles there, the first missile is launched. Arthur the talking computer sacrifices himself to stop the missile before it reaches Earth. They find the evil middle-Eastern leader, "Col. Q" on Mars guarding his missiles. The Mercenaries defeat him, but not in time to reach the remaining missiles before they launch. Their robot companion goes to his destruction in order to stop the launch.