Private Heng Choi serves aboard the Alliance destroyer Peacebringer.

On page 16, Marcine Rume spends some time at a brothel on Bellerophon. This world has been seen or mentioned in previous adventures.

Page 21 describes Jayne's nervousness around River ever since "the incident with the carving knife," though she seemed much more levelheaded since their visit to Ariel. These are references to the events of "Ariel".

On page 24, the crew discuss spider slugs, apparently a pricey delicacy on Londinium. Londinium is the capital planet of the Alliance and is the most like Earth-That-Was. This is the first mention of spider slugs.

Wash has an idea of where the crew may be able to find work, at Golden's Bane, a valley on Zeus' fifth moon. This is the first mention of the valley, the planet Zeus, and the planet's fifth moon in the 'Verse.

On page 26, Wash says he once worked piloting a transport ship for a mining facility on Aberdeen. Aberdeen was previously mentioned as a world known for rhodium mining in Big Damn Hero. Wash here calls it the "butthole of the 'Verse."

Book and Inara go to a space station in orbit around the planet Ghost. According the "The 'Verse in Numbers", Ghost is a planet in the Kalidasa system. This is its first mention in a story.

When Serenity lands in Golden's Bane, the crew remarks on what a dump it is and Zoe adds, "Maybe they've got a Jayne statue somewhere." This is a reference to "Jaynestown", in which the crew visits a backwater where Jayne is considered a hero of mythic proportions and the townspeople have erected a statue of him.

On page 37, Jayne hopes that the potential new job Mal mentions isn't transporting cattle again. Serenity transported a herd through the episodes "Shindig" and "Safe".

On page 40, Gentle invites Mal to a card game of "switch and draw."

On page 61, Wash puts out the call for all crew to report to the mess on the "tannoy."  Tannoy is a Scottish manufacturer of loudspeakers and public address systems. The name has taken on a genericized air in UK public consciousness.

The strange star map leads to an old Generation ship from Earth-That-Was of 500 years ago, named the Sun Tzu. The ship was likely named for Sun Tzu (544-496 BC), a Chinese general and brilliant military strategist, known for writing The Art of War, still studied today in military academies.

    Kaylee tells Simon of having heard there had been over 200 Generation ships and a tale of one of them called the New Tianjin. Tianjin is the name of a major city in China.

    Kaylee also tells that some of the Generation ships never made it to the 'Verse, destroyed in accidents or just vanished along the way. One ship is said to have crashed into one of Heinlein's moons. The planet Heinlein was previously mentioned in the study of "Our Mrs. Reynolds"; most likely, Heinlein is named after the science-fiction author Robert A. Heinlein (1907-1988). 

The Sun Tzu is said to be derelict orbiting an unnamed planetoid beyond the orbit of the gas giant Burnham in the Blue Star system. According to "The 'Verse in Numbers", Burnham was turned into a protostar, the first brown dwarf in the 'Verse to be helioformed and it is the star around which the planet Miranda orbits in "A Better World".

On page 96, as they suit up to board the derelict, Mal sees that Jayne has the gun he calls Boo in a clipped holster on his leg, as well as carrying a shotgun that Mal isn't aware of having a name, but probably does. Boo was first seen in Big Damn Hero, described as a .38 caliber Civil War-styled wheelgun (revolver). That book also states that Jayne has pet names for all of his weapons.

On page 101, Jayne mentions "that Early dude" who went flying off into space. This is in reference to the bounty hunter Jubal Early in "Objects in Flight", whom Mal sent flying off into space with nothing but an EVA suit. He later reappears in "Leaves on the Wind" Part 1.

As the away team maneuvers around the exterior of the derelict in space, looking for and failing to find an entrance lock on page 101, Jayne remarks, "Should've gone straight for that blast zone like I said." But it was Kaylee who suggested entering through one of the damaged areas on page 99, not Jayne.

Page 112 states that the gravity on Serenity is a by-product of the ship's drive.

Pages 119-120 reveal that Kaylee had always thought that Earth-That-Was had been a system of worlds. The paintings she finds in the saloon on the derelict ship show her that it was only one world.

On page 120, Kaylee ruminates that in whatever poisoned and damaged form it was in now, she'd never see Earth-That-Was. Years later, she does get to visit it, thanks to the Alliance portal rings in the 12-part comic book story "Return to Earth-That-Was".

On page 122, Jayne remarks that rich people on Anson's World might buy old Earth-That-Was books to line their walls to make them look intelligent. According the "The 'Verse in Numbers", Anson's World is a planet in the Red Sun system.

The Generation ships held mostly sleeping colonists in suspended animation, but also had generational crews to maintain the ship on its decades-long or longer voyage from Earth-That-Was to the 'Verse.

On page 133, Zoe asks Mal if he remembers Niska and his collection of artifacts from Earth-That-Was. Niska previously appeared in "The Train Job", "War Stories", and "The Ghost Machine".

On page 136, in the derelict, Mal and Zoe discover a hold full Earth-That-Was vehicles, Ford and General Dynamics brands.

On page 139, Jayne mentions Osiris. Osiris is a wealthy world of the central planets of the Alliance.

On page 142, Jayne shoots down an Alliance sentry drone on the derelict. This is the first appearance of such a device.

River tells Silas there is a myth or legend about him at the Academy, that he is the first one they made, the one where everything went wrong. Silas responds, "Everything went right."

On page 198, Wash again confirms that Serenity has no weapons, as seen in past stories (except "The Other Half", where Serenity suddenly is able to blow up a Reaver ship chasing Mal's hovercraft).

On page 213, Kaylee recalls the time River "shot those men." This refers to events at the end of "War Stories".

On page 222, it turns out Wash does not really know the species of his famous dinosaur toys.

Niska's torture of Wash (and Mal) mentioned on page 224 occurred in "War Stories".

On page 230, the Hands of Blue reflect that Silas is more human than them. What are the Hands of Blue?

On page 234, Simon reflects on his sister being an experimental subject of Dr. Mathias. Mathias was the head of the team that imbued River with her special abilities and damaged her mind, as seen in "The R. Tam Sessions", "River Run", and "Triggered".

On page 237, Simon recalls another pair of the Hands of Blue who almost captured River and himself on Ariel. This occurred in "Ariel".

On page 248, Kaylee does not look forward to getting shot again. She was shot in the stomach by Agent Dobson in "Serenity" and saved by Simon in surgery.

On page 322, Jayne pulls out some of the "loot" he pilfered from the old Earth-That-Was ark. These include "a mug with a weird smiley mouse's face on the side" (probably a Mickey Mouse mug) and a medical book, Diseases of the Inner Ear (there are actually several different real world books going by this title by different authors from 1860-2015).

On page 323, Wash is excited that another item in Jayne's loot is a Taurus watch, of which he says, "Legend has it they only made a thousand of these, back on Earth-That-Was." As far as I can tell, this is a fictitious item.

At the very end of the novel, after having escaped Silas' influence, River states, "I saw what I could become. And I learned that if I allow that to happen, there's nothing in the 'verse that can stop me." In "War Stories", River, borrowing a phrase said in jest by Kaylee, said, "No power in the verse can stop me." 

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