Or, where it all began. As the story begins: Two of the most enduring characters in the canon are introduced right in the opening panel. Note that Bruce smokes a pipe; this used to be a sign of sophistication and intelligence for men. Reed Richards was often shown smoking a pipe in early Fantastic Four issues.
Having Commissioner Gordon be a friend of Bruce's is an important (although mostly forgotten) part of the early series. It enables Bruce to get information that the police have but which has not been released to the press. In this case, it actually introduces Bruce to the crime, as the Commissioner soon learns that Lambert, the "chemical king", has been murdered. Bruce tags along to gather information, and meets the accused killer, Lambert's son, who insists he's innocent.
Bruce hangs around long enough to get the information he needs on Lambert's former partners (Crane, Rogers and Stryker). Crane calls to tell the commissioner that he's received a death threat, but before the police can arrive, he's shot dead by an intruder. Batman confronts the killer and an accomplice on the roof: Incidentally, that panel appeared (redrawn) in Justice League of America #37 in the mid-1960s; see here.
He easily defeats the crooks. According to the text, he puts the shooter "in a deadly headlock" and throws him off the roof of a two-story home. He recovers a document that the criminals had taken from Crane. This page also features the first appearance of Batman's red car (precursor to the Batmobile): Meanwhile, Rogers, the other member of the former partnership, has gone to Stryker's home in a panic. He is clubbed by Stryker's assistant, who it appears is behind the murders: Batman rescues Rogers from death by gassing (first deathtrap in Batman), and kayos Jennings. But it turns out that Stryker himself was actually behind the killings, and to save himself from being shot, Batman punches the chemical magnate, who falls through a railing and into a vat of acid. He wastes no time on false compassion: The story ends with Bruce Wayne listening with a rather bored attitude to Commissioner Gordon's recital of the facts. Stryker had killed his former partners because they had sold him the business and he wanted to avoid paying off the amount he owed them for their shares. Gordon remarks to himself afterwards that Bruce must lead a rather boring life as he is so disinterested in everything. But at Bruce's home, he is revealed to actually be the Batman himself. As Bill Jourdain noted in a Comic Geek Speak interview awhile ago, this of course comes as no surprise to us with the benefit of 70+ years of the character, but back in 1939, this probably came as a shock to the readers.