A group of small comet-obsessed aliens worship Jenny after she is mistaken for their "comet goddess". It's fun at first, but they soon drive Jenny crazy. However, when confronted, the aliens promise to leave her alone after one last ceremony. Jenny unwittingly pulls the Sun toward the Earth, as the aliens wish to turn the Earth into a comet. To save Earth, Jenny uses the same ceremony in the opposite direction, and then hurls the aliens’ spaceship into an elliptical orbit around the Sun, turning them into a comet. The Earth is saved, but someone's missing...

It turns out, unbeknownst to Jenny and everyone else, Sheldon accidentally stowed away with the comet aliens!

"Good Old Sheldon" is the sequel to this episode.