SUPERGIRL Report Reveals James Gunn and Craig Gillespie Clashed Over Creative Direction, Test Screenings, and Competing Cuts

The story behind Supergirl’s disappointing theatrical run keeps getting more interesting. After the film struggled with critics, audiences, and the box office, a new report has revealed what was happening during post-production.

According to The Hollywood Reporter, the movie ran into creative conflicts between James Gunn and Craig Gillespie, rough test screenings, competing edits, and a last minute scramble to get the film into shape.

According to the report, Gunn and Gillespie had “creative differences over the direction of the movie,” and the film “never found its footing in the post-production process.” One insider summed up the situation by saying:

“‘They were not creatively aligned’ is the polite way of describing things.’”

Other sources insisted the disagreements were simply part of the creative process and described the friction as “healthy,” but concerns reportedly surfaced almost immediately after principal photography wrapped in May 2025.

Both DC Studios and Gillespie reportedly realized something wasn’t clicking, and when the first major test screenings were held that December, the results weren’t encouraging. Audience scores, which are measured on a 100-point scale, remained stuck in the 60s.

That led Gunn to bring in Jeremy Slater, whose previous credits include Moon Knight, Mortal Kombat, and the now-canceled The Authority movie. Although Ana Nogueira stayed involved with the screenplay, Slater reportedly wrote, or at least helped write, material for nine days of reshoots as the studio worked to improve the film.

The editing room also became another source of creative disagreement.

Music selections became one of the biggest talking points during testing. A cover of Cyndi Lauper‘s “Girls Just Want to Have Fun” played during the film’s final battle at a February screening, while another sequence featured a cover of Jimmy Eat World’s “The Middle,” a choice that has since been widely criticized by fans.

According to the report, both songs were selected by Gunn rather than Gillespie.

The movie also had two editors working on different versions. Gillespie teamed up once again with longtime collaborator Tatiana S. Riegel, who previously worked with him on Cruella, while Gunn relied on Fred Raskin, who edited Peacemaker.

Although test screening scores gradually climbed into the low 70s, DC Studios reportedly decided to compare two completely different cuts of the movie by holding what insiders described as a “bakeoff.”

As The Hollywood Reporter explains: “It is unclear what major differences emerged, but one source says Gillespie’s version was 11 minutes longer and featured more of the villain, Krem, played by Matthias Schoenaerts.

“When the two competing versions tested, the scores surprisingly dropped significantly, although the studio’s inched out ahead of Gillespie’s…but by only two points, according to sources.”

The report also notes: “Gillespie’s version scored strongly on song choices, pacing and villain. Eking out a win, even a middling one, the studio chose its cut as the one to go into theaters.

“A studio insider says the differences were not particularly pronounced.”

After that, there were no additional test screenings. Gunn ultimately released the version that largely reflected the studio’s preferred cut.

The results speak for themselves. Supergirl currently sits at 54% on Rotten Tomatoes and earned a B- CinemaScore from audiences.

One filmmaker told the trade: “[A bakeoff] happens more than you think, but it’s not normal. If a studio is going to put money into the test process, it means they feel strongly about certain things.”

The report goes on to say that Gillespie eventually had to “advocate” for the material he wanted included, suggesting the theatrical release wasn’t the filmmaker’s preferred version.

Of course, the editing process may have been only part of the problem.

The screenplay itself has drawn criticism for making major changes to the source material, turning what many fans considered a vibrant cosmic adventure into something much grittier.

Nogueira has also inadvertently revealed that she misunderstood the ending of the comic, transforming a story centered on choosing not to seek revenge into something much closer to a Mad Max-style revenge tale.

Despite the reception to Supergirl, Nogueira is still attached to write DC Studios’ upcoming Wonder Woman reboot as well as Teen Titans.

At this point, it feels like Supergirl became the product of competing creative visions instead of one clear direction.

Whether the theatrical cut would’ve been better with Gillespie’s version or whether the issues were baked into the screenplay from the beginning is something fans will probably continue debating for a long time.

One thing seems clear, though. The production hit far more turbulence than audiences ever realized before the movie reached theaters.