The Heat Thing: While exploring the planet Jupiter Jace discovers a molten monster that destroys his ship with a lava bomb. Jace calls for help. Space Ghost and Jan head for Jupiter to rescue Jace. They circle the monster and are hit by a lava bomb. Space Ghost forces the monster back into the lava pit it came from. Jace and Jan use The Phantom Cruiser's heat ray and cold ray to seal the monster in.
Elenco: Don Messick , Gary Owens , Keye Luke , Mike Road , Tim Matheson , Alan Reed , Johnny Carson , Ted Cassidy , Vic Perrin , Ginny Tyler .