O'Brien was stunned. His sidekick on Conan, Andy Richter, was stunned. And his guest for the night, Will Arnett, was stunned.
Soon, the audience was stunned too, as O'Brien broke the news to them, apologizing for having to do it.
"This is absolutely shocking and horrifying and so upsetting on every level, and we're at the end of the show and it felt like it needed to be acknowledged," O'Brien said. "We're absolutely stunned to get this news."
"He was an amazingly kind and generous person and our thoughts go out to his family," said Richter.
"As funny as he was, he was even better as a person, he was one of the loveliest and sweetest and kindest guys I've ever worked with," added Arnett. "It's a major, major loss for everybody."
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