Quote from Stuart in the episode Spoiler: Dexys Midnight Runners Get a Royalty Payment
Kripke: All wight, boss man, how do we accomplish this? Stuart: So the Leonard-Sheldon thingy was never completed. It needs a steering wheel. Denise: A steering wheel? Stuart: Not literally, but some kind of control mechanism to get us back to the time and place before everything went to hell.
