It’s set for release in November 2022 after being pushed back amid the pandemic.
And extras working on The Flash were seen filming a protest for the hotly-anticipated movie, which will star Ezra Miller and Michael Keaton, in London on Sunday.
The actors could be seen waving flags and carrying signs which seemed to tease a new character as they read Jester Judd.
Location shoot: Extras working on The Flash were seen carrying signs which seemed to tease a new character as they read Jester Judd while filming in London on Sunday
The extras all looked casual as they stood together in a crowd and held up their signs, with most of the stars donning face masks.
Several people could also be seen wearing bright orange vests and acting as marshals for the scenes.
In between takes, some of the extras sat with their protest signs on the floor while others managed to perch on a bench.
Leading stars of the movie such as Ezra, Michael and Sasha Calle, who was seen filming in her Supergirl costume last month, were not seen at the weekend shoot.
Protest: Several people stood behind a metal barrier with many donning face masks inbetween takes of the scene
The upcoming movie will see The Flash travel back in time to prevent the murder of his mother, triggering a string of unexpected consequences in the process including meeting Batman in a parallel dimension.
Set for a November 2022 release, filming began in April and took place at various locations in England, with production scheduled to move to Scotland later this year.
The Flash was originally scheduled for release in 2018, although it was later pushed back due to its troubled development process.
After director Andy Muschietti was brought on to helm the film, it was rescheduled for a June 2022 debut and was eventually pushed back to November 4 of that year as a response to the onset of the global pandemic.
Staying safe: Others waved flags while in the protest group with many people donning face masks
Quick break: In between takes, some of the extras sat with their protest signs on the floor while others managed to perch on a bench
Earlier in June, Muschietti, shared a photo of Keaton’s bloody Batman costume to his Instagram account.
The actor was announced to be playing the Caped Crusader in the much-awaited film this past April, although he was first speculated to have been involved with the project in June of last year.
Muschietti’s photo showed Batman’s iconic insignia that is typically placed on the center of the character’s costume. A few drops of what appeared to be blood were notably spattered across its front.
The Birdman star’s first time portraying the character was in 1989’s Batman, which was directed by Tim Burton.
Having a look: Cyclists slowed down to have a look at the protesting extras while out for a ride in London over the weekend
Keaton went on to portray the character in the film’s sequel, Batman Returns, which was also helmed by Burton and released in 1992.
After the Ed Wood director stepped down from a planned third sequel, the Beetlejuice actor also left the series, and the two were replaced by Joel Schumacher and Val Kilmer, respectively.
Other actors who have portrayed the Dark Knight since then include George Clooney and Christian Bale, among others.
Ben Affleck went on to portray Batman in the 2016 feature Batman V Superman: Dawn Of Justice and played the character in several other features.
An inside look: The Flash’s director, Andy Muschietti, shared an image of a blood-spattered Batman logo to his Instagram account earlier in June
The 48-year-old actor was initially supposed to direct, write and star in the upcoming feature The Batman, although he later left the production and was replaced by Robert Pattinson.
Both Affleck and Keaton are set to portray younger and older versions of Bruce Wayne in The Flash.
A film based on the DC Comics character had been in development for several decades, with several aborted attempts to create a movie about the superhero occurring over a period of roughly thirty years.
The feature went through several prospective directors, including Rick Famuyiwa and Seth Grahame-Smith, before Muschietti stepped in to helm the flick.
The Barry Allen version of The Flash will be portrayed by Ezra Miller, who first played the speedster in Batman V Superman: Dawn Of Justice.
Other performers who will appear in the long-awaited movie include Kiersey Clemons, Sasha Calle and Ron Livingston.
The feature will follow the titular character as he travels back in time in order to prevent the untimely death of his mother, which causes consequences to occur in his own timeline.
Putting in work: The Flash has been in development for several decades and is expected to be released in November of next year; Muschietti is seen in 2019