With General Morando searching for Gaylen's Core, Aja and Krel must travel into their parents' subconscious to learn the core's location first.
With General Morando determined to learn the location of Gaylen's Core, Aja and Krel must hurry into their parents' memories to find the core first before Morando. Meanwhile, Varvatos, Steve, Eli, Toby, AAARRRGGHH!!!, Momblank, and Dadblank must escape Kubritz's captivity and venture back to Arcadia to save the royal children.
- Tatiana Maslany as Aja Tarron/Queen Coranda
- Diego Luna as Krel Tarron
- Nick Offerman as Varvatos Vex
- Glenn Close as Mothership
- Alon Abutbul as General Morando
- Uzo Aduba as Colonel Kubritz
- Hayley Atwell as Zadra
- Darin De Paul as Zeron Alpha
- Andy Garcia as King Fialkov
- Cheryl Hines as Momblank
- Tom Kenny as Dadblank
- Laraine Newman as Nana
- James Purefoy as Kanjigar
- Victor Raider-Wexler as Vendel
- Cole Sand as Eli Pepperjack
- Charlie Saxton as Toby Domzalski
- Fred Tatasciore as AAARRRGGHH!!!
- Frank Welker as Luug
- Steven Yeun as Steve Palchuk
- Mother sacrifices herself to reinitialize the stasis chamber so King Fialkov and Queen Coranda can continue healing.
- It is revealed that hundreds of years ago, Fialkov and Coranda had entrusted Kanjigar the Courageous to look after Gaylen's Core after it was nearly stolen by the Zeron Brotherhood on Akiridion-5.
- They have also preprogrammed the Mothership to travel specifically to Earth in the event of an emergency, just in case their legacy ever needs to reclaim it, which Mother herself seems to admit. This pretty much justifies Morando's previous theory from "Mother's Day", regarding why the royals were really sent the Earth.
- It is also revealed that Akiridions can live up to hundreds (or even thousands) of years, much like Trolls.
- It's implied that the Akiridions and Trolls are connected through an ancient prophecy all along.
- When Aja reads off from the kissing tree hundreds of years ago, the only initials on it is RB + CH. This could be a possible allusion to the executive producers of the franchise, Rodrigo Blaas and Chad Hammes.
- Title: The episode's title is a reference to the 1946 film noir of the same name, and by extension the 1939 novel from which the film is based.
- Continuity: Fialkov lampshades Kanjigar's title as "Trollhunter" by stating, "Just so I'm clear, you're a Trollhunter, but you're also a troll. So, does that mean you hunt yourself?" Toby also asks this similar question in the Trollhunters episode "Wherefore Art Thou, Trollhunter?"
- When thinking of ways to reinitialize the stasis chamber, Aja suggests unplugging the pods and plugging them back in, which is a nod to the common phrase "Have you tried unplugging it and plugging it back in again?" Krel lampshades this by saying that such a solution is not applicable to every technical issue.
- When Kanjigar says "For the glory of Merlin, Daylight is mine to command", Aja finds it familiar. It could possibly be a residue memory from "D'aja Vu" since it was the only time she's ever heard Jim say the incantation.