There is a plan in the works to make a Batman Beyond movie. It's one of those vague projects that has no substance to it yet, but maybe by the time the series takes place, the movie will start filming.
Kevin Conroy isn't old enough to play Elderly Wayne without lots of prosthetics and make-up, but he has the perfect voice. Michael Keaton probably wouldn't portray elderly Wayne the way we'd want. He made a good mysterious and antisocial Batman, but I doubt he'd be a satisfactory grizzled curmudgeon who looks like Wayne.
As for Terry, I know that Joshua Jackson (the one decent actor from "Dawson's Creek" and "The Skulls") was/is being considered. I'm not sure if he's too old now, but a few years ago, he would have gotten my vote. He has played a hot-headed ne'er-do-well before, and I think he'd be a good Terry McGillis.
I just got this funny image of Anthony Hopkins as a grizzled, old Batman. Anyone see "Mask of Zorro"? Not a suggestion, just a funny image.
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Conroy is 48 years old. I know they could age him with makeup and latex, but I haven't seen him in action more than once, and I don't know if he should do the part in live action.
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I'm the best there is at what I do, but what I do isn't very nice.
Mel Gibson has this kind of bruce wayne thing going for him he also looks the part if you add a bit more make up. He would be my top choice, and as for batman an up and comer would be the best way possible. Hell i could play him.
Robin Williams? Who is your dealer?? Robin Williams could play Wolverine, though. Look how hairy he is. Just kidding.
I agree that if they aged Mel Gibson with their movie magic, he might be a good choice.
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I'm the best there is at what I do, but what I do isn't very nice.