Robotnik is after the Power Gems from the city of Submerbia and Sonic and Tails are hired to stop him.

Robotnik's insane cousin, Dr. Warpnik, captures Tails and lures Sonic into his Zone of Confusion in order to enact revenge on Robotnik for banishing him.

Robotnik has unleashed his Stupidity Ray on Mobius, knowing that the newly-stupefied Mobians will be too brain dead to stop him.

On Sonic's birthday, Tails builds a flying bicycle. Realizing Tails' potential with mechanics, Professor Von Schlemmer invites Tails to be his research assistant.