The rare book that was auctioned, "The Posthumous Papers of the Pickwick Club", or just "The Pickwick Papers" by Charles Dickens was originally published in twenty serialized parts in 1836. In 2017, depending on completeness and condition, copies signed by Dickens have been listed from $25,000 to $100,000.
When the envelope gets stuck in the door as the murderer escapes the room just ahead of Blackie, half the envelope is seen. A few seconds later when Blackie arrives at the door, almost all of the envelope is sticking out of the locked door.
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