News of Robin Williams' death was received with shock and sadness Monday on social media, with real-world fans and Hollywood celebrities alike expressing surprise and grief over the comic's passing.
"I could not be more stunned by the loss of Robin Williams, mensch, great talent, acting partner, genuine soul," tweeted Steve Martin, whose comedy albums won Grammy Awards in the two years before Williams' breakout "Reality ... What a Concept" LP took the statue in 1980.
"I am in shock," said Marilu Henner, who — like his "Mork & Mindy" costar Pam Dawber — had recently worked with Williams on the TV series "The Crazy Ones." "I had never seen him happier & more positive in all the yrs I've known him."
Comedian Dane Cook found himself "in utter disbelief," while "Supernatural" actor Misha Collins was more reflective: "Breaks my heart that someone who brought so much joy could be quietly suffering so much pain."
Henry Winkler, who starred as the Fonz on "Happy Days," where Williams' Mork character came to life, bid his friend adieu with a memory of what it was like to see him work.
"Robin Williams was like no other," Winkler tweeted. "To watch him create on the spot was a privilege to behold.. Robin you are an angel now !!! REST IN PEACE."
See more celebrity reactions below, and in the story gallery above. Make sure to click open the captions.
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