This book collect Batman stories from Detective Comics #51-56, World's Finest #2 and #3 and Batman #6 and #7, covering material from May-November 1941. These are very strong stories and there's a nice variety. There are two stories featuring signature Batman villains, but also Batman taking on river pirates, old west mysteries, a mystery set in timber country, and of course a good share of good old urban mysteries.
Some highlights of the book:
Viola Vane (Detective Comics #53): Bruce Wayne and a friend get into an argument over whether everyone in Gotham are heartless. Batman gets a chance to show the city has heart when he saves a wanna be actress who has been fibbing to her parents about the success of her career (she's actually a waitress.) Batman gets the city to set her up as a successful actress with jewels and furs. In many ways, this seems more like a typical Superman story rather than Batman. However, when some criminals muscle in on her and try to rob her that adds a nice twist.
The Scarecrow is introduced in World's Finest #3 (that's odd because World's Finest rarely has such fine material.) The story establishes many facts such as his occupation and name. However, the character's use of guns and violence is unusual and something that would be later abandoned.
The Joker has a very solid story leading off Batman #7 when he gets a bunch of practical jokers to start committing crimes for him. little by little. The twisted nature of the Joker is definitely on display in this story as he slowly turns them from regular practical jokes to a life of crime. Though the story is maybe a little over the top in telling kids that practical jokes leads to homicidal mania.
Perhaps, the most important change in the book is the focus of the relationship between Batman and the police. In issue 6, he helps a young patrolman with a tough beat defeat criminals and internal police corruption. Batman #7 features a very solid story, "The People vs. Batman" where Bruce Wayne is framed for murder and it's up to Robin to get the killers and eventually Batman is broken out of jail leading Commissioner Gordon to deliver a speech to the jury on Batman's virtue. In context, it doesn't make a whole lot of sense as to why he would be making this speech in this context, but it's awesome speech. Not only is that, it shows a shift in the characters with Batman being appointed an honorary member of the Police force resulting in Batman and Gordon working close together for decades to come until the relationship would be redefined in the 1980s. That alone makes this a must-read chapter in the Batman story.