John Belushi was reportedly drowning himself in alcohol and drugs while trying to turn around his career during his last days at the Chateau Marmont in 1982, and the last people to see him alive were Robert De Niro, Robin Williams and a woman named Kathy Smith – who later pleaded guilty to involuntary manslaughter for supplying the comedian with his last fatal doses of cocaine and heroin, according to a report on a new book about the hotel.

“The Castle on Sunset,” a book set to be released next month, claims Belushi was at the hotel working on a script that flopped with studio executives, according to The Hollywood Reporter. By that time, Belushi had suffered a string of flops with his last true hit “Animal House,” which was four years old at the time, THR reported.

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Belushi’s frequent missed meetings, dirty appearance, incoherent speech and disgusting hotel room hadn’t gone unnoticed by those close to him and, the book claimed. His wife and Dan Aykroyd were conspiring to get him out of L.A. and back to New York where they hoped they could get him off of drugs. At the time Ackroyd was working on the script for “Ghostbusters,” which he wanted to make with Belushi.

The night before Belushi’s death – March 4, 1982 – the book says friend Robert De Niro and later Robin Williams, partied with Belushi and Smith in his bungalow.

The next morning, Belushi was found unresponsive in his hotel room. Paramedics declared him at the scene. He had died of an overdose.

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Belushi's manager informed Aykroyd of his death and De Niro-- who found out after calling the hotel numerous times-- reportedly dropped the phone and cried when he realized what had happened. The hotel remodeled the room, hoping to avoid cult status, but their efforts failed and tours of Hollywood’s most notorious incidents frequent the hotel. To this day, Chateau Marmont is still synonymous with Belushi’s death.