Christopher Reeve and Robin Williams' friendship could have been enough to save the comedian, according to a close Hollywood friend.

"Super/Man: The Christopher Reeve Story," which premiered at the Sundance Film Festival, shared the actor's legacy 20 years after his death and featured interviews with many who called him a friend.

"I always felt that if Chris was still around, Robin would still be alive," actress Glenn Close said in the film, via The Guardian.

Reeve died in 2004 after a cardiac arrest at the age of 52. He had been confined to a wheelchair after a horseback riding accident left him paralyzed nine years before his death. Williams and Reeve roomed together while attending New York's Juilliard School before they both rose to fame.

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Robin Williams and Christopher Reeve

Christopher Reeve and Robin Williams roomed together while attending New York's Juilliard. (Fotos International/Frank Edwards/Getty Images)

Christopher Reeve in a wheelchair

Christopher Reeve injured his spinal cord and was left paralyzed nine years before his 2004 death. (Michael Stephens/PA Images/PA Images via Getty Images)

Williams and Reeve became closer than ever after the "Superman" star's spinal cord injury. The "Mrs. Doubtfire" actor threw a party for Reeve every year on the anniversary of the accident.

Close has said before that Williams would be alive if Reeves had not died. While giving a speech at the "A Magical Evening" Gala in 2017, the "Fatal Attraction" star opened up about the friendship between Williams and Reeve she observed while filming "The World According to Garp" with the comedian in 1982.

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Christopher Reeve, his family and Robin Williams

Robin Williams and Christopher Reeves stayed close as they both gained fame in Hollywood. (Richard Corkery/NY Daily News Archive via Getty Images)

"On Friday evenings, Chris would literally swoop in, piloting his own plane, scoop Robin up, and away they would fly for the weekend. On Sunday, late afternoon, Chris would swoop back in and deliver Robin back. I have to say a little worse for wear.

"Those were the heady days for them both," she added, via Entertainment Tonight. "They were on top of the world. They were living the kind of fast and crazy life that our business can hand to you if you become a wildly famous phenomenon, practically overnight.

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"Their friendship, their connection, is the stuff of legend. It not only endured, but became a life-giving force sustaining them both," Close revealed. "I am convinced that if Chris were still with us, Robin would be too."

Robin Williams at a film festival gala

Robin Williams died by suicide in August 2014. (Albert Chau/FilmMagic)

In the years before Williams' death in 2014, the actor was unaware he was dealing with Lewy body dementia. Williams reportedly appeared tired while on set and didn't seem to be his usual self before he died by suicide Aug. 11, 2014.

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The comedian was diagnosed with the neurological disorder posthumously after an autopsy was performed. Lewy body dementia is the second most common type of dementia after Alzheimer's. The disease affects brain regions involved in thinking, memory and movement, according to the Mayo Clinic.

The autopsy found no illegal drugs or alcohol in Williams' system.