I recently had the pleasure of interviewing Batman: The Long Halloween supervising producer Butch Lukic, and during our conversation, I noted how Part One and Part Two share the same animation style as Superman: Man of Tomorrow and Justice Society: World War II, which came out in August 2020 and April 2021, respectively. When I asked if this meant the animated Long Halloween existed in the same continuity as those other two movies, and subsequently whether a new shared universe is now being built similar to the
recently-concluded DC Animated Movie Universe, Lukic responded:
Well yeah, initially Long Halloween was the start of all this, but after I almost finished Part One, we got shelved. The Matt Reeves movie, they told us, ‘Well he wants to adapt Long Halloween for his screenplay.’ So we’re out, we have to wait or not get released at all until after he’s finished his film and released it. So the original intention was for Batman: The Long Halloween to be the first movie, and then continue on into Man of Tomorrow, and then next it would have been Justice Society: World War II. But this got shelved for a couple years, so now we’re releasing the final versions now because I wasn’t able complete them until four months ago. Once we got the go-ahead that we could release our version because Matt Reeves’ version isn’t going to be about Long Halloween.