SpongeBob SquarePants Season 3 Episode 2 Club SpongeBob - My Pretty Seahorse >While planting flowers on the first day of spring, SpongeBob finds and adopts a seahorse, and names her Mystery. They become close friends, and when Mystery follows him to work at the Krusty Krab, Mr. Krabs orders SpongeBob to get rid of his pet after causing trouble for the customers. Instead of sending her away, SpongeBob hides Mystery in a cupboard in the kitchen. Mystery still unintentionally causes trouble and after he tells them a story of his early life with a dollar, Mr. Krabs advises SpongeBob to release Mystery back into the wild. So with a sad, heavy heart, SpongeBob does just that.