When director Matt Reeves was writing “The Batman,” and effectively taking the franchise reigns with what was expected to be the first of a trilogy of films featuring Robert Pattinson as the caped crusader, he knew he wanted his Gotham to be a more grounded cinematic world. Inspired by the tone of Frank Miller’s comicbook series “Batman: Year One,” in which the chaotic real world of 1970s New York was a recognizable underpinning, Reeves wanted his Gotham to be recognizable to a modern audience — a direct reflection of our own broken and divisive times. That tone, more so than interlocking narrative, would be the glue.

It’s a vision Reeves had always imagined could neatly spin-off into an HBO-like series, especially when switching out of Batman’s point-of-view in the movies, and exploring the world through the eyes of one of the Rogues Gallery villains.

“They are, even more than Batman,...