It has been six months since Peter, Ray, and Winston returned to the team and defeated two troublesome ghosts. Now Stay Puft, Soul Man, and Louis are back as well. Slimer felt lonely one day and opened the Containment Unit hoping to find a female ghost to make out with. He got more than he bargained for when he freed the Boogieman. The Boogieman was very mad that he had to endure years of imprisonment and was ready to get back at the Ghostbusters. He was a corporeal entity again, so he couldn't just be trapped. Roland adjusted the proton streams so that the Boogieman would become a ghost again so he could be recaptured and restored to the Containment Unit.