He subsequently moved into the Penthouse at the Xanadu Princess Resort on Grand Bahama Island, which he had recently purchased. He lived almost exclusively in the penthouse of the Xanadu Beach Resort & Marina for the last four years of his life. Hughes spent a total of $300 million on his many properties in Las Vegas. In 1972, author Clifford Irving caused a media sensation when he claimed he had co-written an authorized autobiography of Hughes. Hughes was so reclusive that he did not immediately publicly refute Irving's statement, leading many to believe the Irving book was genuine. However, before the book's publication, Hughes finally denounced Irving in a teleconference and the entire project was eventually exposed as a hoax. Irving was later convicted of fraud and spent 17 months in prison. In 1974, the Orson Welles film "F for Fake" included a section on the Hughes biography hoax, leaving a question open as to whether it was actually Hughes who took part in the teleconference (since so few people had actually heard or seen him in recent years). In 1977, "The Hoax" by Clifford Irving was published in the United Kingdom, telling his story of these events. The 2006 film "The Hoax", starring Richard Gere, is also based on these events. Hughes is reported to have died on April 5, 1976, at 1:27 p.m. on board an aircraft, Learjet 24B N855W, owned by Robert Graf and piloted by Jeff Abrams. He was en route from his penthouse at the Acapulco Fairmont Princess Hotel in Mexico to the Methodist Hospital in Houston. His reclusiveness and possibly his drug use made him practically unrecognizable. His hair, beard, fingernails, and toenails were long—his tall frame now weighed barely , and the FBI had to use fingerprints to conclusively identify the body. Howard Hughes' alias, John T. Conover, was used when his body arrived at a morgue in Houston on the day of his death. A subsequent autopsy recorded kidney failure as the cause of death. Hughes was in extremely poor physical condition at the time of his death. He suffered from malnutrition and was covered in bedsores. While his kidneys were damaged, his other internal organs, including his brain, which had no visible damage other than illnesses, were deemed perfectly healthy. X-rays revealed five broken-off hypodermic needles in the flesh of his arms. To inject codeine into his muscles, Hughes had used glass syringes with metal needles that easily became detached.