The Flash movie will feature Ben Affleck's final turn as The Caped Crusader.
Before the film's release later this year, the Oscar winner donned Batman's iconic cape and cowl across four Worlds of DC projects – Batman v Superman: Dawn of Justice, Suicide Squad, Justice League and Zack Snyder's Justice League – while developing and subsequently ditching his own solo movie.
Confirming to The Herald Sun that his work on The Flash "put a really nice finish on my experience with that character", fans will be waving goodbye to arguably cinema's most grizzled incarnation of Batman in November.
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"I have never said this – this is hot off the presses – but maybe my favourite scenes in terms of Batman and the interpretation of Batman that I have done, were in The Flash movie," he said.
"I hope they maintain the integrity of what we did because I thought it was great and really interesting – different, but not in a way that is incongruent with the character."
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As for whether those aforementioned scenes will make it into the final cut of director Andy Muschietti's vision, your guess is as good as ours right now, but the actor remains proud of his contributions.
"Who knows? Maybe they will decide that it doesn't work, but when I went and did it, it was really fun and really, really satisfying and encouraging and I thought, 'Wow – I think I have finally figured it out'," he added.
Meddling with the multiverse, The Flash also reintegrates Michael Keaton's version of the comic book hero, who last stalked the streets of Gotham City 30 years ago in Batman Returns.
The Flash is scheduled for release on November 4.