Young Justice: Outsiders episode 21 is aptly named "Unknown Factors." Every plotline within the episode is driven by unexpected complications that arise in already difficult situations. The heroes find themselves tested as never before and a series of difficult choices are made along the way.

The central story of "Unknown Factors" sees Black Lightning and Nightwing undertaking a recon mission in the mansion of sinister CEO Gretchen Goode that ends with their being captured due to their being totally unprepared to cope with an unknown factor - Gretchen Goode is truly the New God Granny Goodness. This leads to two separate rescue missions, with Kaldur attempting to negotiate the release of his friends and the Outsiders stepping in when that effort falls short. This leads to the revelation that Halo is an unknown factor and the final piece of the puzzle that is the Anti-Life Equation.

Related: Who Is Metron? Young Justice's New God Of Knowledge Explained

The episode's B-plot is focused on Karen "Bumblebee" Beecher and Mal Duncan, as they deal with the birth of their daughter. The prospective parents get to the hospital just before a snowstorm closes the roads, yet they are faced with a whole series of unknown factors as their daughter requires an emergency operation after being delivered. With the hospital's best surgeon trapped by the storm, a still-shaky after labor Karen must use her powers to shrink down and perform the surgery herself from inside her daughter's heart. With big mythology reveals and real-world discussions at play, here are all the biggest questions from Young Justice: Outsiders episode 21, "Unknown Factors."

7. What Is The Significance of The Mysteries Of Udolpho?

Young Justice Outsiders The Mysteries of Udolpho

Both Gretchen Goode and Dr. Helga Jace are seen reading the same novel, The Mysteries of Udolpho, over the course of Young Justice season 3, episode 21. Written by Ann Radcliffe and published in 1794, it is widely considered to be the archetypal Gothic novel, filled with elements of horror and romance. The plot centers around a young French noblewoman, Emily St. Aubert, who is forced to travel with her aunt to the remote and reportedly haunted castle Udolpho, where her new uncle (the bandit king Montoni) holds many people hostage in the castle's dungeons. With the main plot of "Unknown Factors" centering around a mansion where strange things happen and people are held captive, the parallels to The Mysteries of Udolpho are clear.

6. Who Is Dr. Evelyn Fox?

Young Justice Outsiders Dr. Evelyn Fox

Young Justice has become famous for introducing many unknown characters from the comics into its universe in brief cameos. Evelyn Fox, the doctor who delivers Karen and Mal's baby before walking Karen through how to perform heart surgery, might be the most obscure DC Comics character ever to be featured on the show. The original Evelyn Fox only appeared in three issues of an Adam Strange miniseries from 1990, where she was introduced as a new love interest for the title hero.

Adam Strange: The Man of Two Worlds was meant to act as a gritty reboot of the classic Silver Age hero, adding a dark side to the story of a scientist who was continually teleported between Earth and the high-tech world of Rann. The mini-series revealed Rann to be far less of a Utopia than in earlier stories and saw Adam's wife Alanna dying in childbirth, shortly after Adam had an affair with Dr. Evelyn Fox, who was also accidentally transported to Raan from Earth and helped to deliver Alanna's baby. Nothing was ever said about what happened to Dr. Evelyn Fox afterwards, as she was completely ignored by future writers, who pretended the affair had never happened while writing Adam Strange as a grieving widower.

Related: Krypton TV Show's Adam Strange Differs From the Comics

5. Who Are Infinity Incorporated?

The Infinity Inc. team poses as Jade flies above them in a panel from DC Comics.

Just before the Outsiders become aware of Aquaman's plight, GeoForce enters the living room of the Outsiders' headquarters while looking at his phone and asks if anyone else has heard of a group called Infinity Incorporated. There are several DC Comics superhero teams who have used this name, but the most famous one is the original incarnation, who first appeared in the comics in 1984. This version of Infinity Inc. was made up of the children and proteges of the Justice Society of America (such as Batman's daughter, Huntress, and Hawkman's son, Silver Scarab) and was originally introduced as the Earth 2 equivalent of the Teen Titans.

Given comments made by Lex Luthor in Young Justice episode 19, "Elder Wisdom," regarding co-opting the idea of the Outsiders instead of discouraging teenage vigilantism, it seems likely that the group GeoForce is speaking of will be based on the version of Infinity Inc. seen in the 2006 mini-series 52. In that storyline, Lex Luthor began selling metagene therapy to the public, allowing anyone who could afford it to buy themselves superpowers. As part of this "Everyman Project," Luthor created his own in-house superhero team and dubbed them Infinity Inc. after buying the copyright of the original team's name. It seems a safe bet the Young Justice version of Infinity Inc. will have a similar relationship with Luthor.

4. What Is Wrong With Nightwing?

Young Justice Outsiders Sick Nightwing With Oracle

Both Nightwing and Black Lightning suffer greatly at the hands of Gretchen Goode, suspended in some kind of pit that leaves them weakened and completely under Goode's control. This latter fact is hidden from Aquaman and Wyynde when they come to request the release of their allies, until Goode orders the two tortured heroes to attack their friends. Thankfully, it seemed that the healing powers of Halo were able to ease their suffering and break Goode's control on their minds.

Unfortunately, once everyone is safely back at Outsider's HQ, Nightwing seems to take a turn for the worse. He is shown tossing and turning as a worried Oracle watches, apparently unable to wake him from whatever nightmare has seized him. Could whatever torture had been inflicted on Nightwing taken a deeper toll on him than Black Lightning for some reason? Or was Black Lightning just faster to recover due to some unknown x-factor relating to his status as a metahuman or some unique property of his electrical powers?

Related: What To Expect From Black Lightning Season 3

3. Who Is The Ultra-Humanite?

oung Justice Outsiders Ultra Humanite

Young Justice episode 21, "Unknown Factors," finally solves the on-going mystery of Dr. Jace's mentor, revealing them to be the Ultra-Humanite. A brilliant but twisted scientist who placed their brain into the body of an albino gorilla, Ultra-Humanite was introduced in Young Justice season 1, episode 14, "Revelation." However, the Ultra-Humanite did not appear in any other episodes until it was revealed that they had risen to a leadership position in The Light in Young Justice season 3, episode 9, "Home Fires".

Ultra-Humanite's background in the reality of Young Justice was touched upon in the tie-in comic book, which was written by Executive Producer Greg Wiseman and is considered canon. The story revealed that the Ultra-Humanite had previous inhabited the body of an old woman before implanting his brain into a gorilla's body. Though the woman is not named, this could be a reference to the comic book origins of the Ultra-Humanite and how one of his hosts was a screen actress from the 1940s named Delorese Winter, whose work he had enjoyed.

Beyond that, little is known about the Ultra-Humanite, as he claims to have forgotten his real name and history after swapping bodies so many times. Oddly enough, his first form in the comics was that of a cliched bald mad scientist and he was the closest thing Superman had to an arch-enemy until the creation of Lex Luthor. He has also frequently been depicted as a Nazi, though it remains to be seen if the Ultra-Humanite on Young Justice has any such associations. In any case, it is clear why Dr. Jace would choose to consult with the Ultra-Humanite on the subject of saving Halo's life, should they need to find some way of moving her into another new body.

2. Does Halo Hold The Secret Of The Anti-Life Equation?

Young Justice Outsiders Halo Heals Black Lightning and Nightwing

The final scene of Young Justice episode 21, "Unknown Factors, shows Gretchen Goode bowing to a hologram of Darkseid, informing him that she has found the secret of the Anti-Life Equation. While this is not outright stated in the show, it is inferred that the key is Halo, due to Goode's reaction when Halo exhibited the power of a Motherbox while healing her teammates and spoke a strange language identified as that of the Old Gods. Precisely how Halo is the key to the Anti-Life Equation is unclear, but it likely has something to do with her unique nature as a new life form born of humanity and the New Gods' technology.

Read More: Young Justice: Outsiders Reveals Halo Is The Key To The Anti-Life Equation

1. Does Anyone Still Think Young Justice Is A Kid's Show?

Young Justice Outsiders Karen Beecher Mal Duncan and Daughter

Young Justice was famously cancelled after two seasons on Cartoon Network because it appealed more to teenagers and young adults than the target audience of children. With a diverse cast of characters and complex storylines that focused on its characters as people rather than just an assortment of costumes and superpowers, it is no wonder that Young Justice developed a cult following that later morphed into a movement of avid fans that helped win the show a third season. It is also no surprise that the show sailed over the heads of the children to whom Cartoon Network was trying to sell action figures on behalf of their sponsors.

Since the move to DC Universe, Young Justice: Outsiders has grown bolder in introducing more adult content into the series and doing things the censors at Cartoon Network would never have allowed. This includes an increased level of violence and confirming the LGBTQ status of several characters. The show has also sneaked more innuendo into the scripts, such as the Atlantean Wyynde's reaction to breathing air for the first time in his life - "I'll never get used to sucking and blowing like this."

Beyond freely depicting sex and violence, Young Justice: Outsiders has also introduced more mature themes into the series with stories that only older viewers could appreciate. Bumblebee's subplot in "Unknown Factors" is a prime example of this, dealing with both a parent's fear of losing a child and the medical ethics of genetically modifying children so as to eliminate birth defects giving way to designer children. None of this will be relatable to any young children who stumble across the show, begging the question - can anyone seriously believe, at this point, that Young Justice: Outsiders is a kids' show?

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