The Mark: Billionaire Playboy Bruce Wayne.
The Con: Frame him for being Batman.
This is back in the days when Batman is still mostly considered an urban legend and the Gotham City PD is pretty unanimously in "if he is real, arrest him" mode. So Bruce turning out to be Batman would be very bad for him, his reputation, and his business.
The crew is split on whether Batman is real. Nate doesn't believe it, obviously, Hardison and Parker do, Sophie thinks its some gangster running a con to get their competitors out of business, Eliot also doesn't believe it.
So Bruce obviously isn't happy when he hears that there's someone out there faking Batman sightings and casting suspicion on him, so he goes out to figure out what's going on. This means that he leaves during a fancy party he was attending, that Nate and Sophie were also at for con reasons. Meanwhile, Parker and Hardison have to infiltrate Wayne Manor for whatever reason, which has unusually high security for just some rich dude's mcmansion, and because Hardison's a genius and Parker is the world's greatest thief, they accidentally discover the Batcave, only to run into Alfred.
While that's going on, Eliot is faking a Batman sighting only to run into the real Batman. He loses the fight because even though we are following the rule of "Every story with the Leverage crew becomes a Leverage episode" and Eliot is very good, there is no way he beats the goddamn Batman. He does recognize his fighting style means that Batman trained with the League of Assassins, though, because "It's a very distinctive style." Though, of course, Batman doesn't get any information out of him and Eliot is still able to get away.
Cut back to the Batcave, Alfred has Hardison at gunpoint because he's a badass but Parker was still hidden so he didn't find her. And since Parker is Batman tier stealthy, she drops down behind him and tases him. Team Leverage now knows Bruce Wayne is Batman for real. Meanwhile Batman is now aware of Eliot and, because Eliot talks to the others during the fight, is aware that he has accomplices. He's also suspicious of Nate and Sophie because they were acting very strange at the party. And, of course, he's heading to the Batcave so even if Parker and Hardison are gone by that point, Alfred still saw them. Which means Team Leverage/Batman Team-Up! The real villains turn out to be Wayne Enterprises' corrupt and greedy shareholders, who were using Bruce as a scapegoat.
