The video shows the green screen production that went into filming one of the film's scenes, a portion of which has already been leaked online. In the scene, Barry Allen (Ezra Miller) sees that Iris is in danger, after her convertible crashes into a large truck. Barry uses his super speed to break through a window and rescue her.
The behind-the-scenes video shows Clemons in part of her Iris outfit, and being gradually tilted upside down in a rig machine. She then has a conversation with what appears to be Miller's stunt double, before the rig system places her back upright.
As Justice League fans know, this scene was ultimately cut from the finished film, despite fans being very excited for Iris' DC Extended Universe debut. Clemons was pretty hyped up about the sequence as well, in an interview earlier this year.
"I finished all my stuff with Zack [Snyder], I wish him well and I have no idea what's going on right now but I'm sure whatever they're doing is necessary." Clemons revealed. "I know the parts that I did introducing Iris are f---ing sick. I can't wait to see the movie. I'm so happy that I've been introduced to this genre because I didn't really have any type of desire to be a part of any superhero world. And then I stepped on the set of Justice League and I was like, 'Holy s---. All right!'"
But now that Clemons' version of Iris still hasn't been introduced into the MCU, things are still up in the air, including what time period she could hail from.
"Because of going back and forth past and future with The Flash, you don't even know what time period you actually meet Iris," Clemons said in September, in reference to the upcoming Flashpoint film.
Justice League is now in theaters; Aquaman arrives on December 21, 2018; Shazam! on April 5, 2019; Wonder Woman 2 on November 1st, 2019; Cyborg on April 3, 2020; and Green Lantern Corps on July 24, 2020.