Supergirl: 15 Unresolved Mysteries And Plot Holes The Show Left Hanging

In October 2015, Supergirl premiered on CBS. The adventures of the Last Daughter of Krypton continue two and half season and over fifty episodes later. In that surprisingly short amount of time, the show has jumped networks, joined the Arrowverse, expanded its own universe, and saw the rightful firing of its co-showrunner, Andrew Kreisberg.

It also saw a ton of development over the past couple of years from characters to worldbuilding. Equal to that development? The plot of the show, like many Arrowverse shows, also grew with character pasts being explored and new lines followed. Fort Rozz escapees were a plot point in season one, but now its all about fighting Reign. Television will always be a medium that changes with the times. Of course, change can also mean that things get lost in the shuffle.

While the show has engaging characters, its weakest elements tend to come from its plot. Over the course of two and half years, the show introduced and dropped plots with surprising quickness. Some of these plots, however, could have worked given time and attention. Whether it came from the change in network or changes behind the scenes, there are a lot of mysteries surrounding the Girl of Steel. These are 15 Unresolved Mysteries and Plot Holes Supergirl Left Hanging. 

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15 Where Did Earth-1 Get Kryptonite?

Technically, this happened on the Arrow episode of "Crisis On Earth-X," but it affects Supergirl the most. During the second part of the crossover event, Oliver Queen shoots Overgirl with a Kryptonite arrow. Now if both of these take place on the same Earth, then this would not be a question that needs answering.

Supergirl, however, takes place on Earth-38. On that Earth, the DEO destroyed Kryptonite following the whole Metallo incident at the start of season two. Also how did Oliver learn about Kryptonite? Did Kara tell Barry who told Oliver? Did Cisco breach to Earth-38 to pick up some Kryptonite? Or are there actually Kryptonians on Earth-1? The Kryptonite had to come from Krypton. While the arrow definitely helped in the moment, it only serves to create more questions about the Krypton on Earth-1.

14 President Marsdin's Alien Heritage

Supergirl Lynda Carter Olivia Marsdin

Everyone loves Lynda Carter. After all, she did play the first live-action female superhero in the 70s Wonder Woman television show. It’s safe to say that her efforts paved the way for shows like Supergirl to exist. When the announcement came that she would play President Olivia Marsdin of Earth-38 in season two, it delighted fans.

In the two-part season finale, fans learned that Marsdin was a shapeshifting alien refugee from Durla. You think that the show would go somewhere with this. Since the end of season two, however, fans only learned that she made Cat Grant her Press Secretary. It’s a shame that such a compelling plot point seemingly dropped in-between seasons. It could be due to Carter’s availability, but it just seems like a waste. Seriously, not one threat to expose the President’s secret or something? Not one?

13 Kara and James' Romance

Supergirl Episode 7 Kara James Olsen

One of Supergirl’s biggest plots in season one revolved around the blossoming romance between Kara Danvers and James Olsen. Whether or not they have chemistry aside, it did take up about twenty episodes. Misunderstandings happened. They dated different people. At the end of season one, they decided to give this whole dating thing a try. Then, in the opening episodes of season two, Kara dumps him. It felt like it came out of nowhere.

It just all felt super rushed. Even if they broke up because there was no spark, fine. They didn’t even have enough to time to find out if a spark existed. Give it at least five episodes. Then everyone just kind of forgot that the relationship happened until James and Lena kissed. Maybe, if James had more of a purpose in the show, then it would not be as noticeable. Even to this day, the writers still do not know what to do with him.

12 The Guardian

Supergirl James Olsen Guardian Cadmus

Poor James Olsen kind of gets the shaft on Supergirl. After the sudden end of the Karaolsen relationship, the writers decided to make James a hero of his own. Looking at the plan, it makes sense. It’s just no one seems to know what to do with James on the show. Whether or not that plot was rushed is a discussion for another time, but they seemed to have mostly dropped it.

While the recent episode “For Good” did see a reappearance of the Guardian, the plot scarcely was in the episodes leading up to it. While he probably can’t go after the likes of Reign, he could provide some kind of back-up and support. This lack of commitment just sucks for both the show and Mehcad Brooks. The poor guy needs some stuff to do, and not just to be a love interest either.

11 Silver Banshee

Silver Banshee got a decent amount of screen back in season one. In fact, Siobhan Smythe had a whole arc that chronicled her descent in villainy. She starts out as Cat Grant’s second assistant and Kara’s new workplace rival. She has a fling with Winn. When she loses said job, Siobhan inherits her family’s curse that will keep driving her to revenge until she kills the person her vengeance is focused on.

Now Italia Ricci’s availability could probably be the reason why the character hasn’t returned. Outside a quick mention in season two, no one said anything about the character. With Kara’s mother re-casted, the question is why can’t they do the same here? Siobhan had stakes because she was part of their lives. More importantly, she introduced the concept of magic into the Supergirl universe. Another thing which has been sadly ignored.

10 What Can J'onn Do Again?

Supergirl Martian Manhunter Review

Most superheroes possess clearly defined powers with weaknesses. While the powers can fluctuate based on the writer or villain, usually they stay pretty consistent. It’s Writing 101: establish the rules and follow them. For the most part, the writers do stay fairly consistent in terms of regular Kryptonian powers and the various aliens with comic counterparts.

The only one who falls outside of that realm seems to be J’onn J’onzz. David Harewood’s consistently great performances aside, J’onn’s powers are surprisingly still a bit undefined and change depending on the situation. For example, in season one, he totally mindwipes Maxwell Lord’s guard, but cannot read Rick Malverne’s mind in season two? Martians supposedly are one of the strongest telepathic races, but he can’t go up against Psi? He has super-strength and can fly, but hasn’t helped Kara with Reign? These plot holes regarding J’onn’s powers really need to be address

9 How Many Surviving Kryptonians Are Out There?

Clark Kent, as the Last Son of Krypton, remains a key part of the Superman mythos. Naturally, Kara’s existence and others (looking at you Zod) throws a bit of wrench into things. One sole survivor out of a whole planet does seem like a bit of overkill, especially with all the Kryptonians running around. So the question remains: just how many Kryptonians are there?

Astra, Non, and Rozz aside, in season one, Kryptonian soldiers fought with Non and Astra. Fort Rozz is a Kryptonian prison. It stands to reason that there would be other Kryptonians on there. Clearly there were some off-world at the time, if Mon-El’s memories are anything to go by. Just how many other Kryptonians truly remain? A rough number would be nice since they keep appearing as the plot demands.

8 Lyra

Supergirl - Lyra

Poor Winn. His love interests keep on disappearing with the changing of the television season. Although, they do keep screwing him over. Lyra, however, clearly wanted to reform. Her relationship with Winn definitely had its sweet moments. Betrayal aside, her motives to save her brother were understandable. They clearly wanted to make it work. She was even going to be a sidekick for the Guardian. Plus having a very clear alien-human relationship would be nice worldbuilding for the show as well.

With the premiere of season three, however, Lyra firmly disappeared from our screens and apparently Winn’s mind. No one has mentioned the alien woman since three begin. If they did, then no one remembers. Granted, Winn has also suffered a fairly reduced role this season as well due to Jeremy Jordan’s touring schedule. Hopefully, audiences will get an explanation in the near future.

7 Bizarro

Bizarro definitely cuts a tragic character in the Supergirl lore. She was created by Maxwell Lord from a brain dead young woman that he enhanced with a serum derived from Kara’s blood. No longer did she have any concept of self or identity outside of being Supergirl. When Kara broke through to her, her body was already breaking down. The DEO made the decision to put Bizarro into stasis in order to save her life.

So whatever happened to Bizarro? Is she still in stasis? And what about the seven other women that Lord took to do this sick experiment? Was she the only success or is there another Bizarro out there? Can they even cure Bizarro? Or is she just doomed to be in stasis forever? At the least, this character deserves a follow-up episode.

6 Where Is Superman Exactly?

Supergirl Season 2 Trailer Superman

Back in season one, Kara asked her cousin to let her be a hero on her own terms. Her cousin has honored that, only appearing when things are truly dire. Still, when Reign was delivering the all-mighty beatdown on Kara, the question remained “where was Superman?” We understand that Kara didn’t ask for his help, but Reign almost killed her. At the least, he should have like called or something, to ask if his help was needed. Sure, if Kara was any indication he couldn’t do much, but well the offer would have been nice.

More importantly, why didn’t he check in on her? Reign wasn’t shy about her attempt to harm her. Even way back in season one, he would check in on with Messenger or whatever. It showed, at least, that he was concerned about his cousin. The radio silence throughout seasons two and three just feels kind of cold and not like Superman.


While Lillian Luthor made an appearance in “For Good,” CADMUS has been noticeably quiet since the season two finale. After being such a huge force in season two, the absence is noticeable. In the immediate aftermath of the Daxamite Invasion, CADMUS was using it to stir up some anti-alien sentiment. So why wasn’t that plot thread followed?

CADMUS slowly but surely tried to hurt the alien population in any way that they could. Maybe, Lillian’s fugitive status put the remaining members into lockdown. Still, especially in the wake of Reign, CADMUS should be all over this. After all, it's Reign’s doomsday prediction they have been spouting. Lillian, or others in the organization, should capitalize on it. Yet, CADMUS hasn’t been mentioned at all. Now Lillian is in prison. Again. Maybe they’ll appear in the future, but it certainly has been a very, very long time.

4 Jeremiah Danvers

Supergirl Homecoming Kara Alex Jeremiah

Jeremiah Danvers was part of some of the most heart-wrenching moments of season two for the Danvers sisters. His betrayal of his family and friends to CADMUS was equal parts shocking and horrifying. In the interim, he's revealed himself to be a cyborg and has gone on the run. Alex still wanted to bring her father to justice.

Maybe this is due to Dean Cain’s schedule, but Jeremiah has been pretty much forgotten about. Outside of a mention during the engagement party, no one seems to be looking for the wayward scientist. Much like CADMUS, he just disappeared from the show in the third season. Seeing as he is important to Kara and Alex’s characters and backstory, he should make an appearance at some point.

3 Maxwell Lord

For those who find Morgan Edge to be too much of a unworthy human being to exist, Maxwell Lord is probably an option. Lord ran parallel as an entitled male villain with a God complex in season one. Peter Facinelli played the role well with a hint of unstated sleaze and smugness to the role. He even played reluctant ally to Kara and company in the season finale before teaming up with General Sam Lane for…something.

It was a tease for season two. Now the change in networks could mean that Facinelli did not want to move with the show. With such a cliffhanger regarding the character, Lord should have made the move in season two. Even if it meant recasting the role, it just seems like a huge threat was removed from the table for no good reason.

2 Lucy Lane

Lucy Lane, played by Jenna Dewan-Tatum, was another key part of season one. The character’s arc followed her journey from enemy to friend for Kara and company. It made for some interesting television. Plus fans knew that in comics Lucy becomes Superwoman, a government created Supergirl under General Sam Lane. It’s unknown if Lucy would have turned into Superwoman if she stayed, but that is a tantalizing story thread.

Like most of the plots on this list, Lucy was probably dropped due to the move to Vancouver. However, she, like Lord, became too important to the cast to just be dropped off unceremoniously. As far as fans know, she’s still working at the DEO’s desert base. In the intervening seasons, things have been quiet on the Lane front. So is Lucy even with the DEO anymore? Or has she returned to her father’s side? Either way, we’re not seeing Superwoman anytime soon.

1 The Omegahedron

Out of all the mysteries that would have led into season two, the biggest were the pod and what would happen with the Omegahedron. This Kryptonian tech fell into the hands of General Sam Lane and Maxwell Lord at the end of season two. Lane asked Lord to look into how to make it work for them. This small device can be used to power an entire Kryptonian city. Non used it to restore Indigo and power Fort Rozz.

It’s a lot of power to have. General Lane and Maxwell Lord having that power? It definitely sets off alarm bells. And what was done with it? Nothing. Like a lot of things from that season, the Omegahedron plot was dropped when the show moved networks. Nothing on that front has been mentioned since, which is a shame as that amount of power in the hands of those two Supergirl hating people? Well, it could have been interesting.


What other dropped Supergirl plots should be revisited or at least addressed?

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