Strange Tales #114, November 1963.
(By Lee, Kirby, and Ayers)
So, I know what you're thinking: "Wasn't Captain America defrosted by the Avengers in Avengers #4, a few months after this issue was released? So who's this joker?" Who indeed...
Our tale begins as the Human Torch's daily workout is interrupted by some of his college pals. No, I don't know what happened to his secret identity from a couple of issues back either.
Naturally, Johnny Storm is a big fan of Captain America, having read comic books about his adventures when he was a kid. Thankfully, this was in the days before we had a rolling timeline. These days, I guess Johnny would have been read antique comics by his great-great grandfather or something.
Anyway, at the antique car fair, trouble erupts in the form of a couple of ne'er-do-wells who pinch a racing car and race off. The Torch sets off after them, but he's not alone.
The two heroes stop the crooks' getaway, but fall to arguing amongst themselves.
Fortunately, the cops show up to catch the villains. The Torch goes off in a sulk, whilst Captain America takes the credit, the cad! Heading home to meet his girlfriend, the two argue over the merit of the returned hero, with "hilarious" results:
Meanwhile, Captain America is back, and it looks like he's a bad 'un...
While the escaped cons draw the attention of the police, the villainous Cap is robbing the local bank. How very... mundane.
Wait a minute, did he just say "sky-platform"?
Holy crap, he did! This costumed criminal has built or bought some sort of Kirbytech helicopter thing, in order to steal a sack of swag from a crappy little town in upstate New York? Does Lee's plot just get really vague at this point, leaving Kirby to fill in the blanks, or was Kirby making it up as he went along, leaving Lee to try and make some sense of it all?
Anyway, let's plough on, shall we? After parachuting to safety from his Kirbycopter, "Cap" escapes in a truck, pursued by the Torch, who's in for a surprise...
I mean, seriously, what? How organised is this guy? Were asbestos-lined trucks just lying around New York back in the 60s? Or was there a supplier of superhero-inconveniencing traps, based on 5th Avenue, back in those days?
Naturally, the Torch escapes his fate, and captures the Cap impersonator, who turns out to be an old foe of the Torch's, the Acrobat, an incredibly minor villain making, justifiably, his last appearance. Presumably he was kneecapped by whomoever was dumb enough to lend him the Kirbycopter. And the point of this story?
I guess we all know what response that appeal met with. "Hey, assholes! Captain America wears BLUE shorts!"