Possibly the Greatest Comic Book of the Golden Age
In the spring of 1940, less than a year after his first appearance in Detective Comics, Batman finally got his own comic. And what a first issue it was! In this one issue was a re-telling of Batman's origin, the return of his nemesis Hugo Strange, the first (and second) appearance of the Joker, and the first appearance of Catwoman! That's a lot of bang for your buck - or your 10¢, as the case may have been.
The Legend of the Batman - Who He Is and How He Came To Be, is a brief, flawless, two page origin recap that sets the stage for the rest of the issue. With clean, simple art, it makes the perfect prologue.
The rest of the stories were untitled, per the custom of the day; I'll refer to them by the names which they've come to be known:
The Joker - Batman may have had other nemeses introduced before, but the Joker has eclipsed them all to become the quintessential Batman villain; and looking at the Joker's first appearance, it's easy to see why. The Clown Prince of Crime comes across as malevolent, brilliant and devious, capable of not only matching wits with Batman, but pitting himself physically against him as well. A great tale.
Professor Hugo Strange and the Monsters - brings Batman's original arch-enemy back, and this time he has giant monsters of his own making to do his bidding. Of all the stories in the issue, this is the only one without Robin, and the story is probably better for it. Hugo's man-made monsters are incredibly violent, and Batman responds with equal force, tossing Strange from a cliff, hanging one villain by cable from the Batplane, and spitting death from the Batplane's front-mounted machine gun. It's unfortunate that this is often the most overlooked story of this issue - overshadowed by all the other first appearances. If it has any weakness, it's an ending that is a bit overly derivative of King Kong.
The Cat is a mystery set on a yacht. Dick Grayson goes undercover to find out who is after a wealthy woman's priceless necklace. The story seems like it was primarily intended as a way to give Robin a larger role. Batman doesn't show up until halfway through the story (he was supposedly working on some other unnamed case). The story has it's ups and downs. On the downside is Batman constantly moralizing - in one particularly bad instance, he frees the prisoners and lets Robin pummel them to prove a point, then when they've had enough and beg him to tell Robin to stop beating them, he breaks fourth wall and lectures the youth of America:
Well kids, there's your proof! Crooks are yellow without their guns! - Don't go around admiring them... Rather, do your best in fighting them and all their kind!
On the upside is, once 'The Cat' (a much cooler sounding name than 'Catwoman' as she would later become known) is revealed to be a beautiful woman, there is an outrageous amount of flirting and sexual tension between them, including the infamous ' Papa Spank!' line.
The Return of the Joker - has Joker back, and as devious as ever, using means both elaborate (booby-trapped telephones) and mundane (a pair of pistols) to steal, kill and elude capture. The only downside here is one final panel goes to waste devoted not to the story, but to 'The Golden Rule of Robin's Regulars', more moralizing, this time an attempt to get kids to do stuff like help old men across streets, and live by the R.O.B.I.N. acronym: 'Readiness, Obedience, Brotherhood, Industriousness and Nationalism'... uhh... right.
If you wanted to read only one Golden Age Batman comic (or one Golden Age superhero comic, for that matter), I'd recommend this one.