WATCH: The Tonight Show with Jimmy Fallon honors Robin Williams with heartwarming tribute

Jimmy Fallon paid tribute to Robin Williams on Tuesday’s ‘The Tonight Show’ by playing his first appearance on the program from the Johnny Carson days.

“He was one of a kind, one in a million. He was unbelievable,” said a somber Fallon. “He was funny, and he was fast, and he would weave in and out of characters.”

Fallon then played Williams’ first interview on the show with former host Johnny Carson, and the historic moment captures the heartfelt and unpredictable nature that defined Robin Williams’ career.

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