The series follows high school student Courtney Whitmore who discovers the cosmic staff originally wielded by Starman and becomes the inspiration for a new generation of superheroes who become the new incarnation of the Justice Society of America.

Stargirl premiered on DC Universe on May 18, 2020; the first season consists of 13 episodes and also aired the following day on the broadcast network The CW.

One decade after most members of the Justice Society of America (JSA) are killed in battle against the Injustice Society of America (ISA), Courtney Whitmore, a high school student who moved to Blue Valley, discovers the Cosmic Staff of Starman and learns that her stepfather Pat Dugan used to be his sidekick.

After encountering the remnants of the ISA which now include the mysterious Dragon King and his daughter Cindy Burman, Courtney becomes the inspiration for a whole new generation of superheroes[3] and recruits Yolanda Montez, Rick Tyler, and Beth Chapel.

When Eclipso breaks free from Cindy's control, the JSA works to stop him and finds new allies in Jennie-Lynn Scott, Jakeem Williams, Thunderbolt, a rescued Charles McNider, a revived Starman, and former ISA members Solomon Grundy, Sportsmaster, and Tigress.

In the third and final season, the heroes and villains living in Blue Valley become embroiled in a murder mystery after former ISA member Steven Sharpe is found dead, while someone has been spying on them with cameras placed all over town.

[4] Regarding the death of Henry King, Jr., Johns revealed that he always "had a finite story", going "from this almost unlikeable bully to possibly a redeemed hero, and then ultimately die protecting his new friends when facing his father, while also learning a lesson that Courtney imparted on him and apologizing to Yolanda".

The character's return in the season one finale with his father pretending to be his son was done to subvert the "nobody ever dies" superhero trope.

[4] The following roles were cast in November: Anjelika Washington as Beth Chapel / Doctor Mid-Nite,[53][4] Yvette Monreal as Yolanda Montez / Wildcat, and Christopher James Baker as Henry King / Brainwave.

[7][8] The following members of the Justice Society of America were cast in December 2018: Joel McHale as Sylvester Pemberton / Starman,[56] Lou Ferrigno Jr. as Rex Tyler / Hourman,[57] Brian Stapf as Ted Grant / Wildcat,[58] and Henry Thomas as Charles McNider / Doctor Mid-Nite.

[63] In February 2021, John Wesley Shipp was revealed to be reprising his role as Jay Garrick from The Flash, albeit as an alternate version.

[67] The third season trailer confirmed the return of Eric Goins as Steven Sharpe / Gambler, who appeared in the first but was absent from the second.

[80] According to Johns, Stargirl was the first Warner Bros. Television series to use previsualization (a process most commonly used by feature films) for their effects scenes.

[69] Previsualization was handled by The Third Floor, Inc.[72] Johns brought his experience working on the films Wonder Woman (2017), Aquaman (2018), and Shazam!

[68] The series release plans shifted and it stayed in post-production longer to accommodate the broadcast on The CW to accomplish the adjustments that had to be made.

[72] Scenes removed in the first episode from The CW broadcast included: establishing shots of Barbara Whitmore's new job, and Pat's auto shop; an interaction between Courtney and Cindy Burman in the halls of Blue Valley High School that Alex Zalben of Decider said was "clear set-up for later" but helped strengthen Courtney's emotional arc; and Mark Ashworth's scenes as "a mysterious, extremely creepy bearded janitor", which Zalben said was more of "a fun Easter egg that will pay dividends down the road";[86] and Courtney finding a newspaper article about Starman and Stripesy.

[88] The second season of the series airs exclusively on The CW,[46] and premiered on August 10, 2021;[89][90] it also debuted on HBO Max on December 10 the same year.

The website's critical consensus reads: "A stellar series perfect for anyone looking for a little hope, Stargirl is delightful fun the whole family can enjoy".

[136] Daniel Fienberg of The Hollywood Reporter gave a review, calling it "derivative, but should fill the superhero-origin-story-shaped hole in your heart" and wrote: "The result is that a show that is frequently derivative to the point of distraction might actually fill a need for viewers able to concentrate on its occasional charms until better superhero shows return".

[138] After the series' cancellation, it was revealed that a spin-off revolving around Infinity Inc. was planned and that it would have followed the Shade, Jennie, and Todd searching for the other offspring of the original JSA members and help them with their potential abilities.

[142] Stargirl and her team were briefly introduced in the Arrowverse crossover "Crisis on Infinite Earths" in January 2020,[143][144] through archive footage from "The Justice Society" episode.

[143][144] Stargirl from the pre-Crisis Earth-1 had previously appeared in three episodes of season two of Legends of Tomorrow, portrayed by Sarah Grey, between October 2016 and February 2017.

Bassinger added that there had already been preliminary discussion about crossing over with The Flash, and she was hopeful to be able to crossover with Melissa Benoist on Supergirl.

[147] Bassinger reprised the role of Stargirl in the ninth episode of the fourth season of the HBO Max series Titans, titled "Dude, Where's My Gar?