Tom Sawyer, Detective is a novella written by Mark Twain and published in 1896. It is a sequel to The Adventures of Tom Sawyer, published twenty years previously.
Mark Twain is often considered to be the consummate American writer, and The Adventures of Tom Sawyer and Huckleberry Finn are touchstones for American culture, both in the tropes they've introduced and the larger issues they explored. So someone deciding to read "Tom Sawyer, Detective" might expect a tale that is poignant, humorous, topical or insightful. Unfortunately, in plot, in characterization, in humor, and in social commentary, this book falls flat.
Tom Sawyer and Huck Finn are sent to stay with his uncle in Arkansas. Along the way, they meet a jewel thief who explicates his story at great length. They then get to Arkansas, where some other stuff happened, and a body is found, and Tom's uncle is arrested, and then Tom Sawyer has to reveal the real criminal in a Perry Mason courtroom scene. I don't know if the villain actually shakes his fist and says "If not for you meddling kids", but it is at about that level. The plot is explicated at great length, but I can't really say I understood it. There is a great use of dialect, which mostly annoyed me. And despite one or two incidents of Tom Sawyer's wilyness, the characters aren't that interesting or realistic.
I don't know why the great Mark Twain wrote such a lackluster book, but he did. The world took little note, and this book is usually not remembered or recommended amongst his works.