Aziz Ansari took to Tumblr on Friday to post a lengthy tribute to Harris Wittels, writer and co-executive producer for NBC's Parks and Recreation.
"I'm still waiting for the other phone call to let me know that Harris is okay and this was all a horrible misunderstanding,' Ansari wrote. "I don't know when my brain is going to be able to process the terrible feeling that fills my heart with dread and my eyes with tears every 20 seconds when I realize this very special person is really gone."
Wittels died Thursday of a suspected drug overdose. He was 30.
Ansari, who plays Tom Haverford on Parks and Rec, remembered Wittels as an "honest" and "hilarious" comedian.
"His jokes were so weird, unexpected, often brilliantly dumb that they were in that ultra-exclusive club of ones that made comedy people laugh -- and laugh hard," Ansari said.
Ansari shared several pages of their unseen script collaborations and pointed out his favorite bits from Wittels' writing.
"Anyone that was ever in a writers room with him knew he was probably the funniest comedy writer out there. He was just a machine," Ansari said.
Ansari wrote on Tumblr that Wittels was getting treatment for substance abuse and seemed to be moving in the "right direction."
"I hope people reading this realize what a incredibly unique man you were, and what brutal a loss it is for those who knew you and also for those who never had the pleasure," he said.
Parks and Recreation star also remembered Wittels at an event Thursday in Los Angleles.
"So, here's my daily life -- today, I lost a friend," she said. I lost a dear, young man in my life who was struggling with addiction and died."