The Black Casebook is a record of Batman's earlier adventures that featured otherworldly, supernatural, or otherwise inexplicable elements as some of Batman's secret projects.
Robin began having doubts of Batman's sanity and decided to take the Black Casebook from the Batcave to examine it, looking for answers. After learning some of Bruce's obscure past, he decided to scan some of the pages of the book and afterwards, he showed it to Spoiler and to Officer Harper, in order to get a better understanding of the situation.
- Case 1042: "The Pigmy Plot" 
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