This is the Book Mark Twain Allegedly Wrote After He was Dead
As we all know, Mark Twain wrote a lot of books in his lifetime. There is one, however, that he allegedly wrote after he was dead. It's called Jap Herron and it dates back to 1917 with a sordid story about how it was published.
Jap Harron, a novel written from the Ouija Board with an introduction about the coming of Jap Herron with a Mark Twain signature shocked the public when it was published over 100 years ago. Ranker mentions Jap Herron as one of Missouri's scariest stories and legends. They also provide some additional backstory about how Jap Harron came to exist:
In St. Louis in 1916, a group of women used a ouija board to contact dead relatives. Imagine their surprise, then, when instead they allegedly came into contact with the spirit of deceased American author Mark Twain.
Wikipedia takes it from there. They say it was written by two mediums over a 2 year period from 1915 through early 1917. It gained fame when the New York Times reviewed it in September of 1917. Twain Quotes shared this scathing excerpt from that review which included this slam dunk:
The humor impresses as a feeble attempt at imitation and, while there is now and then a strong sure touch of pathos or a swift and true revelation of human nature, the "sob stuff" that oozes through many of the scenes, and the overdrawn emotions are too much for credulity. If this is the best that "Mark Twain" can do by reaching across the barrier, the army of admirers that his works have won for him will all hope that he will hereafter respect that boundary.
Ouch. That hurts even if you're a ghost.
As you might imagine, this didn't sit well with the Clemens family. They filed a lawsuit to try and stop the book from profiting the mediums. It went all the way to the Supreme Court. The funny thing is they couldn't prove that Mark Twain's ghost DIDN'T write it. My understanding is that the publishers agreed to destroy all the remaining copies of Jap Herron.
The conjecture is it's highly unlikely Mark Twain's ghost would have troubled himself with sharing a story like Jap Herron, but the book lives on if only in legend.