One of Mr. Kotter's favorite hobbies is to chase beams of light. Whether the light is coming from a flashlight, the sun, a phone, or the sun hitting a mirror Mr. Kotter enters a trance-like state where his only focus is on "the light." Mr.Kotter believes he can catch the light, and will give up only hours after the light has been put away. His owners wonder if this is perhaps more than a hobby, it may actually be an obsession...