Joss Whedon’s single season, cult classicFireflycontinues to be one of the most influential and popularspace western TV showsof all time. Despite it being just over 20 years since its initial release, fans are still just as passionate about the show as they ever were.

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Firefly’sloyal fanbase was a dominant force in the early days of modern fandom and was likely the driving force behind much of the related media published in subsequent years. With a movie sequel and several in-universe comics,Fireflycanon extends much further than just the 14 original episodes. Though hardcore fans have had many theories over the years, only a few made their way into the show’s extended narrative.

1Zoe Is Pregnant

Zoe Alleyne Washburne is one of the more stoic and unsentimental characters inFirefly,which is part of what makes her character so interesting. As such, she doesn’t seem to be the type to need or want children. However, hints toward the end of the show’s single season caused some fans to hypothesize that she could be pregnant. AsCaptain Malcolm Reynolds’tough second-in-command on the ship, Zoe rarely has time for overt displays of emotions. Her marriage to Serenity’s pilot, Hoban Washburne or more commonly known by his nickname ‘Wash’, is still a relatively happy one and the two are alwaysportrayed as very securely in love.

In the episode “Heart of Gold” they discuss the dangers of bringing a child into the world. Zoe is very clearly still in favor of the idea, which some fans view as foreshadowing. Wash explains that their lives are too dangerous to bring a tiny helpless person into. Zoe dismisses this as an excuse and says: “I ain’t so afraid of losing something that I ain’t gonna try to have it. You and I would make one beautiful baby”.

Firefly - Zoe & Wash kissing

This theory, though further hinted at in theSerenitymovie, is ultimately confirmed in theFireflycomicsFloat OutandIt’s Never Easy. Her pregnancy also features in the comic mini-seriesSerenity: Leaves on the Wind,which is set around eight months after theSerenitymovie. In this series, Zoe’s pregnancy and subsequent birth to Wash’s daughter, Emma, is a key plot point.

2Book Has An Alliance Background

Derrial Book is always a rather mysterious presence onboard the Serenity, and several hints throughout the original series led to some fans believing he hasmuch more of an interesting pastthan he lets on. AmongFireflyfans, there are several theories about his background, chief among them being6 that he has a professional history with the Alliance.

When Book first meets the crew, he describes himself as a simple Shepherd wanting to bring his religion to those who need it. But several small details from the series call this into question. Firstly, Book seems to have an unusual amount of knowledge of hand-to-hand combat, infamous criminals, and high-powered weaponry for a simple preacher.

shepherd book from Firefly

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Secondly, and perhaps most importantly, when he is shot and gravely injured in the episode “Safe” he happens to be in possession of an ID that grants him special access to medical help. Though the audience never learns the details of this ID, it’s made clear that it carries some level of prestigious authority.

Book’s Alliance history is ultimately confirmed in the comicSerenity: The Shepherd’s Tale, which tells the story of Derrial Book’s past. Readers learn that long before he became a Shepherd, Book serves as a spy for the Independent side of the war by infiltrating the ranks of the Alliance army.

River Tam stands over the bodies of dead reavers in the Firefly sequel Serenity

3The Reavers Were Government Made

The Reavers are a considerable to threat to all life in The Verse. Known only as psychotic cannibals who went mad on the edge of space, the Reavers aren’t given much of a backstory in the original show. However, this didn’t stop fans from theorizing that the Alliance had more to do with their creation than simple neglect of its citizens.

WithinFirefly,not much is seen of the Reavers except their ships. Reaver Ships are recognizable as they’ve often been mutilated and run with dangerous levels of radiation which allow them additional speed and power. Whenthe crew of the Serenitycomes across the Reaver’s aftermath, all that is left are disfigured bodies and signs of inhuman cruelty and violence.

Inara Sera against a golden brick background in Firefly

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The sequel movie unpacked the origins of the Reavers and ultimately confirmed the theory that the Alliance had a hand in their creation. The very first Reavers werefrom the planet Miranda, on which the Alliance had been testing a chemical known as Pax. This chemical was meant to eradicate human aggression and anger and thus pacify whole populations.

But in 0.01% of the population, Pax had the complete opposite effect and bent people’s minds into madness and pure savagery. It is that small percentage of Miranda’s population who became Reavers and began to plunder the outer reaches of The Verse.

4Inara Is Dying

One of the defining features ofFirefly’sinfluential and short-lived single seasonis the will-they-won’t-they relationship between Mal and Serenity’s resident Companion Inara Serra. But Inara’s contradictory resistance to Mal’s affections and a few heavy lines about mortality led many fans to believe that she’s dying of some kind of terminal illness.

As a Buddhist, Inara has many interesting conversations with the other characters about mortality and the nature of life. But one particular line fans point to as evidence for this theory comes from the episode “Out of Gas”. When the ship is damaged to the point of disabling the life support, everyone but Mal must escape the ship. Simon Tam says to Inara about Serenity: “I just don’t want to die on it”. Inara’s reply is: “I don’t want to die at all.”

In the first episode, Inara is also seen possessing a syringe with a mysterious black liquid in it. Though the scene suggests it may be a suicide kit in case of a Reaver attack, many fans believed it is further evidence that Inara had some mysterious and fatal illness. Though not confirmed in the sequel movie, this subplot for Inara wasconfirmed by the actressherself and in the audio commentaries for theFireflyDVD collection. The novelLife Signs,a tie-in to the show’s universe, explores this plot as well.

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