Co-director Joe Russo has revealed the film is Marvel Studios' longest ever, though the length could change.

However Marvel's heroes defeat Thanos in next year's follow-up to Avengers: Infinity War, it's not going to happen quickly. In a recent live-streamed Q&A, director Joe Russo said that Avengers 4 is the longest Marvel Cinematic Universe movie yet — at least as it currently stands.

"The running time on Avengers 4 is currently sitting right at three hours. We'll see if that holds," he said during an Instagram chat to promote his new bar, Duello, in downtown Los Angeles. That runtime is likely to change, however. In response to a question about where the movie is in terms of postproduction, he revealed, "We're about halfway through the editing process. We're really just scratching the surface on our VFX shots. There are more than 3,000 VFX shots in the movie; those require a lot of time and thought and energy and effort, and we're very early in the phase of getting VFX done. We've just started work with Alan Silvestri on the score, and we're still editing picture at this point."

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