A troll who has grown tired of living under the Brooklyn Bridge runs away to the city in search of good times, but when his fellow trolls take control of the Brooklyn Bridge, the Ghostbusters come to the rescue.

When Egon's Uncle Cyrus comes to visit, the Ghostbusters learn that he is ashamed of his nephew's line of work. The guys decide to prove to Egon's uncle that ghosts are real, but not all goes as planned.

When Peter takes his date to the Cloisters in New York, warrior spirits spew forth from the tapestries with only one thing on their mind: taking Peter's date back into the tapestries with them, where she will remain forever.