It might be hard to imagine any other actress as Kara Zor-El/Kara Danvers aka Supergirl. Melissa Benoist has enjoyed a monopoly on the role in recent years. In the past, only one other actress (Helen Slater) portrayed the Kryptonian character in live-action. Slater returned to play Kara's adoptive mother Eliza in the CW series.

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The same cannot be said of Barry Allen aka The Flash who has been portrayed by a number of actors in the Arrowverse and by Ezra Miller in the DCEU. However, Grant Gustin is the actor who has played the DC hero the longest. If things had gone differently, both the roles of Supergirl and The Flash in the Arrowverse would have gone to different actors. Four other actresses were considered for the role of Kara Danvers while three were considered for Barry Allen.

Supergirl: Claire Holt

Rebekah Michaelson looking serious in The Originals

Back in 2014, Claire Holt was one of the actresses that were screen-tested for the role of Supergirl. Even though she was one of the favorites, she missed out on the coveted role. No explanation was given for her being snubbed but it was assumed that she didn't get the part because of her commitment to the Charles Manson drama Aquarius.

Holt shot into the limelight when she portrayed the LGBTQ character, Samara Cook, in the teen drama Pretty Little Liars. After leaving the show, she went on to portray the vampire Rebekah Mikaelson in The Vampire Diaries as well as its spin-off series The Originals.

The Flash: Andy Mientus

Andy Mientus in The Flash

Andy Mientus badly wanted to be Barry Allen but he didn't get the part. He was honest enough about how it all went, telling Collider that he was cut quite early. He said: "I got great feedback that said, 'He's not quite the right fit for Barry, but we really like him. He's really interesting. Maybe there's something down the pike."

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Mientus ended up getting the role of former S.T.A.R. Labs employee and supervillain Hartley Rathaway aka Pied Piper in The Flash. Piper was the first gay supervillain to appear in a movie or TV series.

Supergirl: Gemma Atkinson

Gemma Atkinson as Tamzin Bayle Casualty.

British actress Gemma Atkinson was also in contention to play Kara Danvers She even put other projects on hold as she awaited the casting news. Sadly, the decision didn't go in her favor.

Atkinson became known by mainstream audiences after she starred in the British soap opera Hollyoaks, known for its high number of regular cast members. At the moment, the soap opera has 50 regular cast members. Atkinson portrayed Lisa Hunter for five seasons before moving on to the medical drama Casualty.

The Flash: Jeremy Jordan

Jeremy Jordan in Supergirl

Jordan is best known for portraying Kara Danvers' friend Winn Schott in Supergirl. But in another world, he could have been running around in a red suit as the hero Barry Allen.

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At some point, Jordan stepped away from portraying Winn regularly in order to place more focus on theater work, which is his first passion. If he'd become The Flash, he probably wouldn't have been able to do that. It's thus good that he landed a role that allows him to step away for a while.

Supergirl: Elizabeth Lail

Elizabeth Lail in Countdown 2019

Lail has had plenty of good roles in the past decade. She is best known for Princess Anna in the ABC fantasy series Once Upon a Time. Fans will also recognize her as Guinevere Beck from Netflix's psychological thriller YOU. Her character dies in the first season before returning as a ghost in the second.

Despite not getting the part, Lail revealed that she relished the experience of auditioning. She told the Hollywood Reporter: "That was so much fun for me. I loved doing that test. That was my first time acting on the Warner Bros. lot, and that was a career highlight for me at that time. It was really exciting."

The Flash: Justin Hartley

Actor Justin Hartley

Hartley portrayed Oliver Queen aka Green Arrow in Smallville. His version of the character had a light green costume compared to the darker one seen in the most recent version in the Arrowverse. Hartley was briefly considered for the role of Barry Allen but his name was soon dropped in favor of Grant Gustin.

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Arrow co-creator Marc Guggenheim revealed that he tried to get Hartley to reprise his role as the Green Arrow for crossover events in the Arroverse but he failed. Apparently, the actor just didn't have the time to wear the suit again. Most recently, Hartley has had a recurring role in the NBC hit show This Is Us. He also appeared in the controversial political satire thriller, The Hunt.  

Supergirl: Kayla Compton

Allegra Garcia in Iris's office.

Compton has played a Kara before, in the dance dram Making Moves. In 2014, she was among the actresses who auditioned for the role of Kara Danvers but she failed to get the part. Her auditioned tape ended up leaking online.

Luckily, Compton still landed another role in the Arrowverse. She was cast as the reformed criminal and meta-human Allegra Garcia in The Flash. She had a recurring role in Season 6 before being promoted to a series regular in Season 7. She might not have gotten to play the hero she wanted but she still played a hero, nevertheless. Better half a bread than no bread.

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