Marc wants to set up a model solar system. To simulate the sun, he and the others get the largest light bulb they can buy. Only after they blow a fuse do they learn (from a guest) that what they really need is a dimmer. Among the show's adventures: Trini goes to Kitt Peak to see a telescope that looks at the sun. ""The Bloodhound Gang"" must decode a message to start ""The Case of the Missing Bloodhound."" (Concludes in next episode.)