Professor Nebulous is the celebrity scientist, famous for building a base on the moon. However it is later revealed that he is lying and it is infact Dr Decapsule that built the moon base. Professor Nebulous attempts to kill Sam Grant and the gang by sending them to the moon base and trapping them without any oxygen. He does this to get them out of the way while he steals more inventions from Dr Decapsule to keep himself famous. Failing this he agrees to fight Dr Decapsule on the roof of the lab. Professor Bebulous wins the fight but Dr Decapsule pulls out a gun last minute ans shoots him. Professor Nebulous falls from the roof to his death.
Professor Nebulous returns in the season finale when Johnny Thunder ressurects him into Professor Reed's body. After the battle Professor Reed returns to normal.