Seth wants to bring snow home to put on his mum's shelf of prized objects given to her by her kids. When he repeatedly tries and fails to bring the snow back before it melts, he uses science to figure out a way to get it home intact.

Seth pushes himself too hard while excitedly preparing to make presentations to his classmates and gets sick; it takes an encounter with his rival to show Seth that it doesn't matter what his classmates think, as long as he likes what he's doing.

Seth and the other Fancies are forced inside, after the town is invaded by cow-like Truffalo. When Seth traps the Truffalo, he causes an environmental chain reaction that threatens to destroy Fancytown.

While exploring, Seth finds an egg and really wants to know what's inside it. When Pam's egg-hatching instincts kick into gear, Seth will have to learn to trust her.

When Seth borrows Pascal's moustache for a day at the beach, the Triloknights think he's an adult. While Seth loves the respect and attention, he must decide if he's really ready for adulthood.

Seth's desire to help Nancy with her job at the hospital results in chaos after he plays doctor. Seth has to admit his wrongdoing and listen to his mother in order to set things right.