When Egon goes inside the Containment Unit, the following ghosts from that were previously captured can be seen: Slug, Snarg & Zonk (from Ghosts R Us (1986)), Killerwatt (from Killerwatt (1986)), Wat (from Mrs. Roger's Neighborhood (1986)), Ghash (from Slimer, Come Home (1986)) the Sandman (from Mr. Sandman, Dream Me a Dream (1986)), Samhain (from When Halloween Was Forever (1986)), the Pallo Mansion ghosts and the Winged Puma (from Look Homeward, Ray (1986)), and the Sleeping ghost (from Take Two (1986)). The trolls from Troll Bridge (1986) and the Boogieman from The Boogieman Cometh (1986) are not in there as they were never trapped in the first place.
For the TV rebroadcasts, once Lorenzo Music's contract had run out, Dave Coulier redubbed Venkman's lines.
This story makes a reference to Peter Venkman's dad, Jim, who was always away during Christmas on business trips.
This takes place in December 1986.
While posing as the Ghost of Christmas Past, Peter uses a View-Master toy to show Scrooge his past.