Daniel Keyes, 'Flowers for Algernon' Author, Dies at 86

Everett Collection
Cliff Robertson in 1968's "Charlie."

The film adaptation of his novel earned Cliff Robertson a best actor Oscar.

Daniel Keyes, the author whose novel Flowers for Algernon was turned into an Oscar-winning film, died Sunday at the age of 86. He died from complications of pneumonia, his daughter Leslie told The New York Times.

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Keyes published the novella Flowers for Algernon in 1959. He turned the story, which centers on a low-IQ man who becomes a genius, into a novel in 1966. It tied for the Nebula Awards' novel of the year and went on to sell 5 million copies.

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The film adaptation, Charly, earned star Cliff Robertson a best actor Oscar in 1968.

Keyes was born Aug. 9, 1927, in Brooklyn, New York. His other works include the 1981 novel The Minds of Billy Milligan, about a criminal with multiple personalities, and the 1999 memoir Algernon, Charlie and I.

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He is survived by his daughters, Leslie and Hillary Keyes, as well as a sister, Gail Marcus.