As per Dresden Files usual Shout Outs abound in the series' fifteenth novel.
- Evidently Harry and Thomas built a dock on Demonreach, which Harry promptly dubbed the Whatsup Dock.
- Harry calls Nicodemus a psychopath, and Nicodemus responds with "Sociopath, actually". Strongly reminiscent of Sherlock.
- In another Sherlock reference, Nicodemus flicks Uriel in the nose to remind the latter that he's technically powerless in the situation, as C.A.M. does to John.
- When Ascher belittles Murphy's height, Harry says she "represents the Lollipop Guild."
- When Ascher and Harry are at the dress party to collect Valmont, they both eye the buffet table rather hungrily. When Ascher questions if they should raid the table, Harry replies that, "even Pitt and Clooney had to eat."
- While in Hades' vault, Harry and Michael quote Monty Python and the Holy Grail (inadvertently on Michael's part).
- After opening the final Gate to Hades' vault, Harry is asked what he thinks is in the vault. He responds with "Fortune and glory, kid. Fortune and glory."
- While recovering Harvey, Harry quotes both The Terminator and Big Trouble in Little China. Harvey doesn't pick up on either line, leaving Dresden somewhat exasperated.
- Even better, after quoting the Terminator, Harry is forced to protect Harvey from some gun-wielding goons the same way the machine protects John Connor in Terminator 2: Judgment Day — By holding the guy against him and turning his back — protected by spell-armored leather — to the onslaught of bullets. By far the biggest shoutout to a movie since Proven Guilty.
- The Big Trouble reference is also a Call-Back, as Harry said the same thing to Will waaaaaay back in Welcome to the Jungle. She didn't get the reference either.
- Dresden later quotes The Black Hole, which someone has seen—Goodman Grey reacts to this quote with some degree of incredulity, which he berates Harry on, saying "nobody remembers that movie." They then spend a few minutes discussing the movie. In the middle of the heist.
- Star Wars:
- When Harry and Bob—possessing a lion statue—conspire to "fight" each other in order to give Butters a chance to escape Binder's goons, Harry can't help but shout lines referencing a similar ploy in A New Hope.Harry: Watch out, he's loose! He'll tear us all apart! I'll get him! [shoots fire "at" Bob, hitting goons]
- There's an extended reference when Butters picks up Fidelacchius and it becomes a lightsaber, sound effects and all.Butters: "Nice try?" Mister, where I come from, there is no try.
- When Harry and Bob—possessing a lion statue—conspire to "fight" each other in order to give Butters a chance to escape Binder's goons, Harry can't help but shout lines referencing a similar ploy in A New Hope.
- When meeting Nicodemus and hearing how raspy his voice is since the strangling Harry gave him, Dresden spits out, in a very Sean Connery fashion, "my cut hash improved your voish," referencing Ramirez in Highlander.
- Dr. Horrible's Sing-Along Blog gets a nod when Harry describes Nick's crew as his own Evil League of Evil.
- Kringle's statement that Kringle and Vadderung are (legally speaking) two different people who just happen to share the same body is quite similar to the explanation given for Admiral/Steadholder/Duchess Harrington's situation, even down to the wording.
- Maggie's room is reportedly full of colorful cartoon ponies. Given this series and author love of referential humor one wonders which ones those may be. It would make a lot of sense given that it’s a series where persons empowered by their virtues do battle with evil creatures of (arguably) spiritual significance, and prefer to redeem them rather than destroy them... really sounds a lot like being a Knight of the Cross. Not to mention being lead by an incredibly powerful wizard who added great "spiritual" powers to her own, taking her beyond the realm of the merely mortal. It could be said to symbolize BOTH her fathers.
- At the beginning, when Harry is describing what some of the inmates of Demonsreach are saying, one of them is quoted as saying "BLARGLE SLORG NOTH HARGHLE FTHAGN (sic)"
- Another of the prisoners is notably British, calls Dresden a novice, tells him to piss off, and calls him "boy". This right after the previous reference, too. Angleton, much?
- Harry mentions twice he needs to set the Wayback Machine.
- In the final chapter, Harry tells Molly that “Home is where, when you go there and tell people to get out, they have to leave.” In the final chapter of The Vor Game by Lois McMaster Bujold (of whom Jim Butcher is a noted fan), Aral Vorkosigan says to Elena Bothari-Jesek, "Home is where, when you have to go there, they have to take you in."
- Which is, in turn, a shout out to Robert Frost's poem The Death of the Hired Man.
- Harry and Ascher complain about real fire Salamanders being "so much bigger than in those Xanth books".
- When the caper crew is commenting on how Harry handled his gate he responds with "Thanks, I'm auditioning for the sequel to Frogger in a week."
- Harry's cue to Grey is a quote from Private Hudson in Aliens.Game over, man. Game over.
- When visiting Mac's, Harry states that he is low on cash, but "I will gladly pay you Tuesday for a sandwich and a beer today", a reference to the character of Wimpy from Popeye.
- When he wants to catch Ursiel's attention, Harry (while flipping him off) calls the Fallen Angel "Yogi".
- He also mentions that given his command over all kinds of monstrous spirits, Hades is possibly the one person in the universe who could actually give the order to release the Kraken.
- Binder says "I love it when the posh bird talks dirty." A reference to Dog Soldiers, which Butcher had previously referenced in Small Favor.
- Probably unintentional, but the description of Nicodemus booking it sound extremely similar to the villain Cicada from The Flash (2014) series.
- Harry's tendency to shout "PARKOUR" during his Le Parkour training may be a shout out to Achievement Hunter's Ray Narvaez Jr who had a tendency to do the same thing whenever attempting the slightest jump.
- Harry explicitly compares the riches in Hades' vault to Smaug's treasure hoard, if Smaug had "crippling levels of obsessive-compulsive disorder and fanatic good taste."
- Fending off Tessa in the bank vault, Harry tries for a quip, but the best he can do is, "Psycho much?" In other words, he's calling her a Psycho Mantis.
