William J. Monahan (born November 3, 1960) is an American screenwriter and novelist. His second produced screenplay was The Departed, a film that earned him a Writers Guild of America Award and Academy Award for Best Adapted Screenplay. Monahan was born in Dorchester, Massachusetts. He attended the University of Massachusetts Amherst, where he studied Elizabethan and Jacobean drama. He moved to New York City and contributed to the alternative weekly newspaper New York Press and the magazines Talk, Maxim, and Spy. In 1997 Monahan won a Pushcart Prize for his short story "A Relation of Various Accidents Observable in Some Animals Included in Vacuo". Monahan was an editor at Spy during the magazine's final years, where he would come in at the close of the monthly issue to rewrite articles and improve jokes. Monahan wrote a novel titled Light House: A Trifle, and Warner Bros. optioned the film rights. In 1999 Talk magazine debuted, and Monahan contributed a travelogue on Gloucester, Massachusetts, to the first issue. In 2000 Monahan's first novel, Light House: A Trifle, was finally published, and it garnered critical acclaim; The New York Times proclaimed, "Monahan's cocksure prose gallops along" and BookPage Fiction called Monahan "a worthy successor to Kingsley Amis." In the second half of 2001 Monahan wrote a fictional column at the New York Press under the pseudonym of Claude La Badarian, which ran for 13 weeks. Warner Bros. optioned the film rights to the novel Light House: A Trifle. The screenplay adaptation has not been produced. Light House was released in 2000. A few years later, he bought back the rights and took the novel off the market. In 2001 20th Century Fox bought Monahan's spec script Tripoli, about William Eaton's epic march on Tripoli during the Barbary Wars, in a deal worth mid-six figures in American dollars, with Mark Gordon attached as producer. The script was given to Ridley Scott to direct. Monahan met with Scott to discuss Tripoli, and Scott mentioned his desire to direct a film about knights. Monahan suggested the Crusades as a setting, reasoning that "you've got every conceivable plot imaginable there, which is far more exotic than fiction". Scott was captivated by Monahan's pitch and hired him to write the screenplay for Kingdom of Heaven. Tripoli was eventually shelved, but Monahan retained ownership of the screenplay and therefore the right to consider new offers at a later date. Monahan steadily secured work in the film industry throughout the 2000s. Brad Pitt's production company, Plan B, hired Monahan to write an adaptation of Hong Kong director Andrew Lau's gangster film Infernal Affairs. Monahan respun Infernal Affairs as a battle between Irish American gangsters and cops in Boston's Southie district, and Martin Scorsese directed the completed screenplay under the title The Departed for Warner Bros. Monahan's work on the film would later earn him two Best Adapted Screenplay awards, from the Writers Guild of America and the Academy Awards.

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