New York City. Kid scientists Peter Venkman, Ray Stantz, and Egon Spengler are investigating ghosts and other paranormal activity in the city. They see their first ghost (Slimer) in the NYC Public Library and that leads them to create the Ghostbusters, setting up their "club" in an old firehouse. Soon, business is booming as the kids are recruited to capture ghosts throughout the city. Winston Zeddemore and Janine Melnitz become the club's first two important additions. But there is something sinister happening at an apartment building and the Ghostbusters must put a stop to it (and the Stay Puft marshmallow man) before the city is overrun with ghouls.