Melissa Benoist's Supergirl is one of the most beloved heroes of the Arrowverse. Here are the show's best episodes.

Supergirl started on CBS in 2015, before joining The CW the following year, wrapping up in 2021. Melissa Benoist was a perfect choice for Kara Zor-El/Danvers, embodying the character with strength, compassion, and an emotional depth. Throughout Supergirl's run, Kara was loved, hated, weakened, emboldened, even lost altogether, yet both the character and the show never lost touch with its optimism, its diversity, and its theme of friends as family. Paired with some of the Arrowverse's best action sequences and villains, Supergirl earned its place as one of DC's best. Here are thirteen of the great episodes that got it there.

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Kara Zor-El's pod crashes on Earth, after being frozen in time for 24 years. Her cousin Superman rescues her and takes her to the Danvers, where she is adopted as one of their own. Forward twelve years, and Kara Danvers is an assistant to Cat Grant (Calista Flockhart), head of CatCo. A news report shows that a plane is about to crash in National City. Kara, knowing her sister Alex (Chyler Leigh) is aboard, uses her powers to save the plane. Now embraced by the public, Supergirl gets a suit and learns how to follow in her cousin's footsteps.

After her fight with Red Tornado (Iddo Goldberg), Kara's powers are drained, leaving her human until they come back. Saddled with a cold and a broken arm, Kara refuses to sit back doing nothing and ventures out to help others, even stopping a gun-toting robber using only her words. Meanwhile, the earthquake has freed dangerous telepathic alien Jemm (Charles Halford) from his underground cell at the Department of Extranormal Operations (DEO), forcing Alex and Hank Henshaw (David Harewood) to lock it down.

Two things make this episode stand out. The first is how it sets up Supergirl as a strong, aspirational figure. Secondly... Hank Henshaw is the freakin' Martian Manhunter, J'onn J'onzz!

Kara assists firefighters with a satellite crash. The fire extinguished, Kara staggers, red glowing veins appearing on her face briefly. She thinks nothing of it and flies away, not seeing red glow amongst the debris of the crash. It turns out the red glow is from red synthetic Kryptonite, created by Maxwell Lord (Peter Facinelli). The red Kryptonite impacts Supergirl severely, leading her to become more confident, abrasive, bullying and destructive. Lord admits that Supergirl's infection is accidental, and creates an antidote. Kara is stopped, and though remorseful she will have to win the trust of the city back.

After being knocked out of a window by Siobhan/Silver Banshee (Italia Ricci), Kara is caught by the Flash, Barry Allen (Grant Gustin). Barry explains to her, Winn (Jeremy Jordan), and James (Mehcan Brooks) about the multiverse, and how he came to their universe. Seeking their help in getting back to his Earth, Flash helps Supergirl in stopping Silver Banshee and Livewire (Brit Morgan) before he and Kara work together to create a breach back to his Earth.

This episode is notable for being the first to include a character from the Arrowverse, and the first time a character from The CW crossed over to a CBS series.

The spacecraft Venture explodes on its first flight, prompting Kara and her cousin Clark (Tyler Hoechlin) to aid at the scene. Believing Lena Luthor (Katie McGrath) may be behind it, they investigate, eventually to discover that it was perpetrated by a terrorist named John Corben (Frederick Schmidt), hired by Lex Luthor to kill Lena.

This is the episode that introduces both Tyler Hoechlin as The CW's Superman, and McGrath as Lena Luthor.

Kara and Clark work together in National City before he returns to Metropolis. However, they run into Corben, who has been turned into a Kryponite-based cyborg named Metallo. Supergirl is seriously injured, prompting an angry Clark to confront Hank about Kryptonite being smuggled out of the DEO. A second Metallo begins wreaking havoc in the city, but Kara and Clark are able to defeat them with anti-Kryptonite gear fashioned by Winn. Hank allows Clark to take the remaining Kryptonite, leading to a reconciliation of the two.

The episode begins with an epic battle between Supergirl and Superman, impacted by Rhea's (Teri Hatcher) silver Kryptonite. Supergirl defeats him, affirming her as Earth's champion. She challenges Rhea to single combat, a Daxamite tradition. Despite overpowering Rhea, Rhea explains that the Daxamite invasion will continue, even if she is killed. Supergirl and Mon-El (Chris Wood) activate a device made by Lena that seeds the atmosphere with lead, deadly for Daxamites. While it stops the invasion, it also means Kara loses her love, Mon-El. Downtrodden, Kara talks to Cat, who manages to turn her frown upside down... and lets it slip that she knows Kara is Supergirl.

Mysterious symbols begin popping up all over National City. Upon investigation, Supergirl discovers that it's the mark of the World Killer, from an ancient Kryptonian prophecy. The World Killer is introduced as Reign (Odette Annable), who battles Supergirl across National City, before she knocks Supergirl unconscious. Sadly, we also learn that Reign is Samantha Arias, a friend of Lena and Kara's, who is unaware of her second personality's actions.

This episode begins with our heroes trying to help people in the wake of natural disasters brought on by the terraforming of Earth. J'onn's father M'yrnn (Carl Lumbly) stops Reign and the terraforming by communing with the Earth, ending his life but saving countless others. As Reign and the Children of Juru gear up for another go, they are stopped by Kara, J'onn, Mon-El and Alura (Erica Durance), resulting in battle. Samantha, now separated physically from Reign, plunges the Sword of Juru into Reign, killing her but not without dire consequences. Distraught, Kara uses Mon-El's ring to time travel back in order to bring Samantha, Reign and herself to Juru, where Samantha overpowers Reign, banishing her forever.

Three years back, Lex Luthor (Jon Cryer) poisons the entire courtroom at his sentencing, before going to serve thirty-two life sentences. However, Lex has bribed and blackmailed the warden, allowing Lex to come and go. Lex is contacted by Kaznian officials, who let him know about a duplicate Supergirl, the Red Daughter, who's currently in Siberia. He gains her trust and slowly manipulates her into an insatiable hatred of America, and Supergirl. This episode cements Cryer as being one of the best to play Luthor.

Lex appoints himself US Secretary of Alien Affairs, following his selfless actions in protecting America from Kaznian attack (cough, cough). He invites Lena and Lillian (Brenda Strong) to the White House and tells them his master plan. He has been transporting captured aliens to Shelley Island, fatally draining them of their powers for an energy source, and to power a weapon that will kill Superman at last. Despite his plan falling apart, he teleports back to his lab, where Lena shoots him. Before "dying", he manages to tell Lena about Kara's secret identity, spinning it as Kara and her friends lying to her for years. The impact of that revelation would drive much of Season 5.

The phenomenal Arrowverse crossover event, based on the classic 1985 DC storyline, kicked off on Supergirl. An antimatter wave is destroying parallel universes, and is about to hit Earth-38, Supergirl's Earth. The DEO and Lena Luthor work to evacuate Earth-38's inhabitants before it's too late. Meanwhile, the Monitor (LaMonica Garrett) has assembled heroes from across the multiverse, explaining to them the need to stop the Anti-Monitor. This first hour of the event is spectacular from start to end, even with the (SPOILER) death of Oliver Queen (Stephen Amell).

Mxyzptlk (Thomas Lennon), to make amends, comes to Kara and offers her the opportunity to travel back in time and tell Lena Luthor the truth about her being Supergirl before Lex Luthor does. If Kara likes the outcome, the timeline will be cemented, otherwise she can go back and try again. After multiple visits back in time, recalling many past storylines, the results all end poorly, which prompts Kara to decline Mxyzptlk's offer. Instead, she confronts Lena, telling her that if Lena can forgive her then she will be there, otherwise Kara will treat Lena as any other villain. Fun fact: This episode made Supergirl the first female-led superhero TV series to hit 100 episodes.

I am Lloyd Farley: irresistibly handsome, intellectually superior, charming and most of all, humble. I am a Canadian and have written a number of short-stories on my Vocal account, many puns and op-eds on my Facebook. I also have published a book, "Pun And Grimeish Mint", a full collection of wholly original puns told in "mini-stories".

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