Watch a trailer for Robin's Wish, a documentary about Robin Williams' last days

It wasn’t until after Robin Williams’ autopsy that doctors discovered the actor was battling a deadly neurodegenerative disorder, one that left him struggling with anxiety, insomnia, and, per his widow, “scary altered realities.” Called Lewy Body Dementia, it will be explored alongside Williams’ final days in a new documentary, Robin’s Wish.

“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,” Susan Schneider Williams, the actor’s widow, said in a statement. “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. And what I discovered along the way was bigger than me, and bigger than Robin. The full story was revealed during the making of this film and it holds the truth that Robin and I had been searching for.”