The Necronomicon is a legendary, mythical grimoire (a textbook of magic) that has appeared in several different realities. Little is known about it except for scattered rumors. According to the illumination upon the cover, the Necronomicon was crafted by a sorcerer named Abdul Alhazred. In the early 20th century, it was one of several occult artifacts sealed within a special museum of the castle keep of Baron Hans von Hammer.
In 1945, a Nazi corporal recovered the Necronomicon (along with several other items) from the ruins of the castle and brought it to Berlin in the hopes of giving it to Adolf Hitler. Hitler was already dead by this point, and the book fell into the possession of the Nazi magus, Anton Arcane. Arcane never had the opportunity to use the grimoire, as his own secret laboratory had been burned to the ground as a result of a B-17 bombing raid. Though a powerful artifact such as this surely survived the Battle of Berlin, its current whereabouts are unknown. 
In a parallel reality, the Necronomicon was said to have been bound in human flesh and its pages scripted in human blood. At varying points, this item was in the possession of the reluctant anti-hero Ash Williams. 
The Necronomicon is a fictional book appearing in the stories by horror novelist H.P. Lovecraft. It was first mentioned in Lovecraft's 1924 short story "The Hound", written in 1922, though its purported author, the "Mad Arab" Abdul Alhazred, had been quoted a year earlier in Lovecraft's "The Nameless City". Among other things, the work contains an account of the Old Ones, their history, and the means for summoning them.
Many readers have believed it to be a real work, with booksellers and librarians receiving many requests for it; pranksters have listed it in rare book catalogs, and a student smuggled a card for it into the Yale University Library's card catalog.
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