Robin Williams' tragic suicide took the world by surprise in August 2014. Six years on, his widow wants the world to understand the nature of the disease that was tormenting him in his final months, via a documentary titled Robin's Wish.

In the early days following Williams' death, which occurred at his home in Tiburon in Marin County, his widow Susan Schneider Williams sought to dispel rumors that drugs or alcohol had played a role in his death. She issued a statement to the media explaining that Williams was suffering from "the early stages of Parkinson's Disease," and this is likely what drove him to his tragic end, along with an ongoing battle with depression.

But two years later, Schneider Williams went public with further details about the specific condition he was suffering from, known as Lewy Body Dementia (LBD), named for early Parkinson's researcher Frederich H. Lewy. The condition involves Lewy Bodies, or abnormal protein deposits, that clog up a person's brain. While on the same spectrum as Parkinson's, LBD is an opposite extreme in which most of the initial symptoms are neurological, not physical. And an autopsy several months after his death revealed that Williams had a particularly extreme case, and that he had been misdiagnosed with Parkinson's.

"All four of the doctors I met with afterwards and who had reviewed his records indicated his was one of the worst pathologies they had seen," Schneider said. "He had about 40% loss of dopamine neurons and almost no neurons were free of Lewy bodies throughout the entire brain and brainstem."

Now, in the new documentary, we hear one expert explain that while Williams was clearly suffering, it's often the case that brilliant people tend to get by longer and deal better with the symptoms of degenerative diseases like this. "Robin Williams was a genius," he says.

We also hear from director Shawn Levy, who directed Williams in one of his final films, the third installment of the Night at the Museum series. Williams had a panic attack on the set of the film and was having trouble remembering his lines — something highly out of character. "I remember him saying to me, 'I don't know what's going on. I'm not me anymore,'" Levy recalls.

Schneider says in a new statement about the film, "Armed with the name of a brain disease I’d never heard of, I set out on a mission to understand it, and that led me down my unchosen path of advocacy. With invaluable help from leading medical experts, I saw that what Robin and I had gone through, finally made sense — our experience matched up with the science."

As for the film's title, Schneider explains to Entertainment Weekly, "Robin wanted to help all of us be less afraid. That was Robin’s wish. We had been discussing what we wanted our legacies to be in life; when it was our time to go, how we wanted to have made people feel. Without missing a beat, Robin said, 'I want to help people be less afraid.'"

The movie will be released on demand, on streaming platforms, on September 1.

Previously: Robin Williams's Widow Opens Up About His Final Days, Dementia

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