The Mysterious Stranger is the final novel attempted by the American author Mark Twain. He worked on it periodically from 1897 through 1908. The body of work is a serious social commentary by Twain addressing his ideas of the Moral Sense and the "damned human race".
Twain wrote multiple versions of the story; each is unfinished and involves a supernatural character called "Satan" or "No. 44".
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