A spin-off of the beloved Batman: The Animated Series, Batman Beyond takes place 40 years in the future. An aged Bruce Wayne has long since retired, a victim of his outdated methods and deteriorating health. However, he happens to meet a teenager named Terry McGinnis, who learns about Bruce’s secret cave. After his father is murdered, Terry steals the Batsuit and pursues his own sense of justice. Seeing himself in Terry, Bruce agrees to train and support the kid as the next Batman.

Batman Beyond ran for 52 episodes across three seasons and has continued in various animated movies and comic books, achieving its own cult status. It is exactly the type of story that would fit in James Gunn‘s vision of the DC Universe, one in which fan favorites such as Creature Commandos and Booster Gold get attention. And it’s exactly the type of caped role that Affleck should have played.

By this point, grouchy and secluded versions of Bruce Wayne are common to the big screen. Christian Bale’s Bruce began The Dark Knight Rises as a recluse, having apparently hidden in his house for seven years. In The Batman, Pattinson’s Wayne shuns the spotlight, ignoring even his company’s business. And Affleck himself portrayed Bruce Wayne as a man who had temporarily given up his masked identity, only returning when Superman arrived on the scene.

The Bruce Wayne of Batman Beyond is totally different though. This Bruce Wayne has been retired for 20 years. Alfred is long since dead. Robin was kidnapped and tortured beyond recognition by the Joker. His only acquaintance is Barbara Gordon, the one-time Batgirl and current police commissioner who has left him in the past, embittered. He’s completely alone and not used to being around people until a man very much like himself arrives.

This type of Bruce Wayne would have given Affleck room to be completely unpleasant and an irredeemable grouch to an almost laughable degree. But it also would have called on him to show surprising warmth, to win over the audience, even if he doesn’t seem to want us on his side. Affleck could play the older Bruce as the same big and abrasive supporting personality he portrayed in Air and The Last Duel. And as he did in those movies, he would still charm us with his infectious personality.

Of course we’re saying all of this right when Affleck’s saying again today that he’s done with superheroes. And of course there’s no Batman Beyond movie currently on the books. But given that Affleck is currently 52, the same age as Bruce at the time of his retirement (and a very important number for DC), there’s still plenty of time for him to change his mind and decide to return to the world of superheroes again… the grouchier the better.