After the Ghostbusters' encounter with a Spawn of Cathulhu, Egon Spengler decided the team needed to consult with a scholar more knowledgeable with the Old Ones. He and Peter Venkman took a flight to Arkham's Miskatonic University to meet with Alice Derleth. After being apprised of the situation, Derleth decided to go back to New York and assist the Ghostbusters. They confronted the Cult of Cathulhu at Wagner's Occult Shop. The Cult summoned a Shuggoth but Derleth saved the team by casting a magic spell that froze and disintegrated the entity.
After leaving the Occult Shop, Alice joined the Ghostbusters in researching a means to stop Cathulhu, before heading out to Coney Island, where Egon predicted was the best place to awaken him. When they arrived, the Cult had already used the Necronomicon to awaken Cathulhu. The Ghostbusters' Proton Packs were unable to defeat it, and Alice was forced to use a different incantation to try and stop him. However, Cathulhu was too powerful to be affected, unlike the Shuggoth, and shrugged off her spell.
Alice was then witness to the Ghostbusters' attempt to destroy Cathuhlu by ionizing the metal rollercoaster, which Peter lured the Old One towards by shooting it in the head, and attracting a lightning bolt that was enough to send Cathuhlu back into hibernation.
After the threat of Cathulhu was ended, Derleth extended her stay in New York to go with Peter and view exhibits of the Eltdown Shards at the Natural History Museum and the Zanthu Tablets and Pre-Druidic Petroglyphs at Columbia University.
- Alice's last name is a reference to August Derleth, a publisher and contributor to the Cthulhu Mythos.
- Omitted from the episode, Alice Derleth translated the "Mystery of the Worm" from Latin. 
- Alice's quote is from H.P. Lovecraft's "The Nameless City."
- The spell that Alice chants to turn the Shuggoth into stone - "Duppira al-kushni, askupati ani kalatum!" - was first uttered in the Dungeons & Dragons episode "Day of the Dungeon Master" also written by Michael Reaves.
- At the end of the episode, Alice mentions the Natural History Museum and Columbia University.
- On page seven of Ghostbusters Issue #5, Alice makes a non-canon cameo in Manhattan.
- Marsha Goodman (2009).The Real Ghostbusters- "The Collect Call of Cathulhu" Episode Commentary (1987) (DVD ts. 09:16-09:19). Time Life Entertainment.
- Marsha Goodman (1986). Episode Call Sheet and SAG Report - "The Collect Call of Cathulhu" (1986).
- Egon Spengler (2009).The Real Ghostbusters- "The Collect Call of Cathulhu" (1987) (DVD ts. 8:36-8:40). Time Life Entertainment. Egon says: "There's a woman named Alice Derleth up in Arkham, Massachusetts who might be able to help us."
- Egon Spengler (2009).The Real Ghostbusters- "The Collect Call of Cathulhu" (1987) (DVD ts. 08:57-09:01). Time Life Entertainment. Egon says: "A renowned academician with a PhD. in Occult Sciences."
- Reaves, Michael (2009). The Real Ghostbusters Complete Collection Volume Two Disc Five, p. 16. CPT Holdings, Inc.
- Alice Derleth (2009).The Real Ghostbusters- "The Collect Call of Cathulhu" (1987) (DVD ts. 09:33-09:39). Time Life Entertainment. Alice says: "That is not dead which can eternal lie, And with strange aeons even death may die."
- Alice Derleth (2009).The Real Ghostbusters- "The Collect Call of Cathulhu" (1987) (DVD ts. 21:22-21:32). Time Life Entertainment.