Scenario where Bruce Wayne and Clark Kent meet before Batman and Superman do, and it actually takes them a long while to clock each other.
Bruce Wayne is a guest at a big charity function in Metropolis. Ordinarily he wouldn't go, but the function is part of a network of concerted efforts against the NRA and to push for better control and reduced school shootings, so he has skin in this game and an appearance by a famous philanthropist who was orphaned by a gunman is kind of a big part of the PR going on. So he makes time for it.
Clark Kent has been assigned to cover the event by the Daily Planet. Given that Bruce Wayne's presence and perspective are a big part of the whole shindig, he does his reporterly duty and makes an effort to get some quotes from him as part of his article. He's not really surprised to discover that despite Bruce Wayne's reputation as a playboy and unreliable party-hard kind of rich boy, he's very serious about this particular topic, because he did his homework and he's put together the pattern that despite appearances, Bruce Wayne does indeed take some things very seriously.
Clark and Bruce sort of recognize each other as men who have some experience in wearing elaborate social masks. Clark figures Bruce plays up the party boy image as a coping mechanism, to keep the tabloids talking about something other than the violent murder of his parents perhaps, while Bruce is not sure why this seemingly mild-mannered reporter has the mien of someone who knows exactly how to use body language and preconceptions to get the reactions he wants from people, but there are a lot of reasons for someone to pick up those skills. Especially an interviewer.
Bruce fake flirts, Clark plays up being flustered, both of them are kind of genuinely into it even though they're both aware the masks are on. It's fun, like roleplay.
Anyway the article comes out great, and Clark manages to get more out of Bruce than just the token soundbites, so the next time there's cause for the Daily Planet to send someone to cover a Wayne event Perry is just like, Kent you do it. Eventually the two build up a working relationship where they're both kind of like, actually there's way more to that guy than meets the eye, and everyone else is like are you sure you don't just want to fuck him? Because it seems like you might just want to fuck him.
Up until a point Clark hadn't really used any of his powers to observe Bruce, though, because he doesn't just do that for no good reason on principle.
But then there's one interview where it's clear that something is just wrong with Bruce Wayne. He's acting "normal", on the surface, maybe even more friendly than usual, but his body language has subtly changed, he's spending an awful lot of time sitting down, and despite his claims of a hangover, he isn't actually showing the symptoms. Clark, long familiar with the process of "turn on the 'X-ray' vision to see if someone's got an undiagnosed health issue and then try to work a doctor's appointment into the conversation" does that, and finds that Mr. Bruce Wayne is somehow sitting at a scheduled interview with a fractured wrist and two broken ribs, plus innumerable signs of past injuries.
So now Clark's trying to figure out who is physically abusing an adult billionaire, or if this is a sex thing.
The superhero identities don't come into it until after Bruce sees Clark take a bullet that he claims "wow just barely missed", and immediately figures out that he's Superman.
