When Billy crashes his bicycle, he obtains a free tricycle from a mysterious boy in a supernatural porta-potty. While Billy loves his tricycle, which he calls Trykie, he is also mocked because of it by Irwin, Pud'n and Sperg. Following this, Trykie moves on his own, and attacks the three of them. Later, Mandy realizes the problem with Trykie, and Grim confirms that he is cursed. Finally, Billy realizes that Trykie is evil, and he lets Mandy destroy him once and for all.