One of the problems with running the "Arrowverse" (the series of inter-connected TV shows that began with 2011's Arrow) is that the showrunners of the series do not have complete control over their characters. They are beholden to their parent company, Warner Bros., who sometimes has plans for characters that differ from what the people running the TV shows have planned and whenever there is a conflict, the television series are never going to win out.

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Meanwhile, there are plenty of other factors that could lead to a plot change, like an actor suddenly becoming unavailable or, in the alternative, an actor becomes available who did not seem like they were going to be available. Or heck, sometimes it is simply a matter of the story changing from its original intention. Whatever the reason, there are a number of planned plots for shows within the "Arrowverse" that never came about. We'll list for you 15 examples of "Arrowverse" plots that almost happened... but then didn't.

15 WHO'S YOUR DADDY

Probably the single biggest alteration to a planned plot happened during the first season of Arrow. Throughout the season, Oliver Queen (Stephen Amell) had been taking down people in a list given to him by his father of people who have "failed" Starling City. As it turned out, however, one of those people was Oliver's own mother, Moira Queen (Susanna Thompson). It turned out that she was working with the evil Malcolm Merlyn (John Barrowman) to create a sort of culling of the "bad" elements of Starling City (their plan involved destroying the poor areas of the city).

Originally, Moira working with Merlyn was going to be because she had an affair with him and Oliver would be revealed as Merlyn's biological son! They decided against that, but ultimately revealed that Merlyn was the son of Oliver's sister, Thea, instead! That would have been a major change to the series.

14 MAD LOVE

In Season 2 of Arrow, we were introduced to the Suicide Squad, a team of criminals that Arrow and John Diggle had taken down in the past. Now, Diggle has to work alongside them to recover a stolen nerve agent. Diggle agrees to do it, but he has problems trusting the organization, ARGUS, that is in charge of the Squad.

At the end of the episode, John is arguing with his former wife, Lyla Michaels, when a mysterious woman offers them counseling. Voiced by Tara Strong (the voice of Harley Quinn in the Arkham games), she was clearly meant to be Harley. Her first appearance was intended purely as an Easter Egg, but there were plans for her to return for a full appearance that were squelched by Warner Bros.

13 BLAME IT ON BROADWAY

At the end of the first episode of Supergirl, there was a shocking twist. We had met Supergirl's mother, Alura, who was played by Laura Benanti. However, at the end of the episode, we learned that the leader of the prisoners who had escaped after Krypton exploded was none other than Alura's twin sister, Astra, also played by Benanti.

Astra was set up as the major villain in season 1 of Supergirl, but then was shockingly killed mid-season. Why the change of plans?. Supergirl producer Andrew Kreisberg explained, "Unfortunately due to Laura's Broadway commitments, we were forced to end Astra's story at this point. But Laura will appear again as Alura, Kara's mother. And it's our fervent hope that we get to have Laura on Supergirl for many years to come." As it turned out, Alura was recast with Erica Durance for season 3.

12 BRANDON ROUTH WAS ALMOST...

One of the hardest things for the producers of the shows within the "Arrowverse" is trying to deal with which characters that Warner Bros. allows them to use. You would be surprised to find out which characters turn out to be off-limits for whatever reasons. It could be something as obvious as "Character X is getting his own movie, so he's off limits" to as obscure as "Someone is thinking about developing an Aquaman cartoon, so no Aquaman in anything!"

When Arrow cast Brandon Routh to play a businessman rival to Oliver Queen (as well as a possible rival for Felicity's romantic attention), the initial intent was for him to play Ted Kord, the Blue Beetle. The powerless Beetle would have fit in well. However, Warner Bros. had something going on with Beetle, so he was off limits. Thus, Ted Kord became Ray Palmer, the Atom!

11 GOING ROGUE

Wentworth Miller as Captain Cold

It's funny how often a TV series can be thrown out of whack by an actor being too good. What we mean is that sometimes, a minor character does such a great job that other shows want them for bigger (often starring) gigs. Or, in the alternative, the show itself will like a character so much that it changes everything. For example, Felicity Smoak was supposed to be a one-shot character and she became the female lead of Arrow!

Similarly, Wentworth Miller's Captain Cold was so good that instead of having him build up the Rogues on Flash, like they originally planned, he became a part of the Legends of Tomorrow spin-off. Then Miller's previous show, Prison Break, returned and Miller had to be written off of Legends, as well. Miller was so good that he went from one "Arrowverse" show to two to none!

10 SUICIDE SQUAD... DOA

In Season 2, Arrow introduced the concept of the Suicide Squad into the series. One of the major characters in this plotline was Floyd Lawton, the killer known as Deadshot. He and John Diggle had a tragic connection, which is that Lawton killed John's brother, Andy (of course, Andy later turned out to be alive).

When Warner Bros. began plans on a Suicide Squad film, however, they quashed the Arrow version of the team and in Season 3, Lawton was killed off. Willa Holland (Thea on the show) recalled, "We were actually trying to build that on our own on the show, and I guess once DC found out they were going to be doing their own movie of it, we had to ax all of the characters before we even got to show them, which was a little annoying at first."

9 STALLED AT THE STARTING GATE

Barry Allen made his debut mid-way through the second season of Arrow, in the episode "The Scientist." He showed up in Starling City to help investigate a mysterious robbery. He was a big fan of the Vigilante and when Oliver was struck down with a deadly drug, Felicity revealed Oliver's secret to Barry so that he could save Oliver's life. At the end of the second part of Barry's debut, he returns home and is blasted by the explosion of the Central City particle accelerator.

The original plan was for Barry to return in two episodes at the end of the season to serve as an official backdoor pilot for the Flash. However, executives were so confident in the Flash that they were fine without any backdoor pilot. So instead, those episodes had Barry still in a coma but introduced his co-workers, Cisco and Caitlin, who give Arrow some help.

8 IF AT FIRST YOU DON'T GET VIXEN...

One of the most interesting additions to the "Arrowverse" was Vixen, played by Megalyn Echikunwoke (who sometimes credits herself as Megalyn E.K.). The reason why she was so unique is that she debuted as a cartoon! Yes, the makers of Arrow were given the chance to produce an animated series for Warner Bros. and Vixen was the character that they wanted to use. Echikunwoke voiced the character, who then guest-starred in live action on Arrow, with Echikunwoke again playing the role.

However, when it came time for the Legends of Tomorrow to add Vixen to their team, Echikunwoke's schedule didn't allow her to join the show as a regular. So instead, they used time travel to have her grandmother, the previous Vixen, join the team instead. The Megalyn Echikunwoke version of Vixen will guest-star in Season 3.

7 A PRESIDENT FOR TWO WORLDS?

On Supergirl, a big aspect of the show is "legacy casting," which is to say that the show has gone out of its way to cast actors and actresses with past connections to the DC Universe. For instance, Supergirl's adopted parents on the series are played by Helen Slater (who played Supergirl in the 1984 film version) and Dean Cain (who played Superman in the 1990s TV series). Teri Hatcher (Lois from the aforementioned 1990s Superman TV series) also joined the show in Season 2.

So, of course they managed to find a role for Lynda Carter, who famously played Wonder Woman on TV in the late 1970s. Carter plays Olivia Marsdin, the President of the United States. The original plan was that Carter would also play the President on the alternate Earths of Arrow and Flash, but ultimately that was deemed to be too complicated to do.

6 SLAMMED INTO A WALL

Clearly, one of the biggest problems for Arrow has been their inability to use certain characters once Warner Bros. determines that they are needed in other media. This is especially true for characters used in film. If a character is starring in a film, Warners doesn't want them to also be a recurring character on a TV show. That was why the Suicide Squad met their end on Arrow.

However, even after the Squad left, the organizer of the Squad, ARGUS head Amanda Waller, remained on Arrow. With Suicide Squad set to be released, though, even Waller had to be removed from the show in 2016. So she was killed off by a group of rogue former special forces operatives called Shadowspire. This led to Lyla Michaels taking over as the had of ARGUS.

5 TEAM FLASH ALMOST HAD ONE MORE MEMBER

In the continuity of the Flash TV series, there were two members of the STAR Labs team that were not present in the first episode of the show. One was Caitlin Snow's missing fiancee, Ronnie Raymond, who was thought to be dead (he later became Firestorm and then sadly did die in battle). The other was the former prodigal son of Harrison Wells, Hartley Rathaway.

Rathaway later became the villainous Pied Piper. However, later on in season 3, when Barry traveled back in time to season 1, he ended up changing history and Hartley became a good guy when Barry returned to the present. That, interestingly enough, was what he was originally going to be on the show. In the original script for the pilot, he was also part of the STAR Labs team. He actually designed Barry's suit (with an ex-firefighter boyfriend as his inspiration).

4 TATTOO YOU

Throughout Arrow's run, Oliver Queen has had a number of tattoos on his body. The theory being, of course, that he got these tattoos during the five-year gap that the world believed that he was dead. Thus, as the series progressed and the flashbacks continued, we would learn where he got the tattoos and, presumably, the significance of them.

However, one of the tattoos that Oliver has one of his side was intended to be explained during Oliver's time spent in Hong Kong in the flashbacks shown in season 2 of the series. They never got around to doing it, so instead, in season 4, it was revealed to be a magic tattoo placed there by John Constantine. It's pretty funny how, if you hang on long enough, plot points can tie in differently than expected.

3 WHO WAS ALMOST THE RAVAGER?

In season 2 of Arrow, Isabel Rochev was introduced as a businesswoman who attempted to stage a hostile takeover of Queen Consolidated. Luckily, Oliver managed to keep her from gaining a controlling interest. Instead, the two shared a 50/50 control of the company. The showrunners were unclear whether they wanted to make Rochev outright evil or not, but in the end, they decided to make her Deathstroke's partner in crime, the Ravager.

Early on in developing season 2, though, the producers originally had another idea in mind when it came to the Ravager. Originally, Deathstroke's female partner was going to turn out to be the (not so dead after all) Sara Lance! Instead, she became the first Canary and was a hero. Sara later joined the Legends of Tomorrow, so that would have changed a whole lot in the "Arrowverse."

2 THE DEADLY FIRST VILLAIN SPOT FOR THE FLASH

In the first episode of the Flash, the original villain was Clyde Mardon, who gained the ability to control the weather, along with his older brother, Mark. In the comics, Mark Mardon was known as the Weather Wizard and that's the role that Mark Mardon ended up playing on the Flash TV series, so why, then, was Clyde the initial villain and not Mark?

Well, you see, the issue was that whomever was the villain in the first episode was destined to be shot in the head by Joe West in the climactic moments of the episode. The first villain was actually going to be The Mist, but they didn't want to kill him. So they instead used the fact that Mardon did have a brother in the comics to make him the fall guy in the first episode.

1 THE ORIGINAL ARROW ENDING

As you might have noticed, Arrow's first episode opened up with Oliver Queen being rescued after being stranded for five years (or so he appeared). Beginning in season 1, then, the show would do flashbacks to the corresponding year that Oliver was missing. As it turned out, he was only on the island for the first two years and then went on a number of adventures before returning to the island to be saved.

Arrow was originally planned to last precisely five years, so that the final episode would end with Oliver getting rescued off of the mysterious island he was stranded on, so the whole thing would be complete, like a circle. However, the show obviously has now gone on past five seasons, rendering the original ending moot.

Which of these plots would you most liked to have seen actually happen? Let us know in the comments section!