CALIFORNIA, UNITED STATES: On what would have been Robin Williams' 70th birthday, 'Harry Potter' director Chris Columbus shared that the late actor would have brought a unique interpretation to the character of Remus Lupin, had he been cast in the role.

Despite the requirement for all actors in the franchise to be British, Janet Hirshenson, the casting director for 'Harry Potter and the Sorcerer's Stone', acknowledged that Williams would undeniably have been brilliant in the role.

Robin Williams wanted to play Hagrid

As per reports from Insider, the late Robin Williams expressed interest in being part of the 'Harry Potter' films. He had a particular desire for the role of Rubeus Hagrid, the beloved half-giant gamekeeper and Keeper of Keys and Grounds at Hogwarts.

Despite Williams' undeniable talent, both Columbus and JK Rowling had made a firm decision to cast only British actors for the Harry Potter series, a commitment that Columbus upheld throughout the casting process.

"I had a conversation with Robin Williams, who wanted to play Lupin," Columbus told the Huffingpost in 2016. "It was very difficult for me to say 'It's all British. There's nothing I can do'”. Columbus added, “Robin would have been brilliant. It would have been a different interpretation - I thought David Thewlis was great - but Robin would have been brilliant”.

William’s wasn’t even given the opportunity to audition

Williams’ first choice was to portray Remus Lupin, a role that was eventually given to David Thewlis. While Thewlis delivered an excellent performance, Williams would have been a fantastic choice as well. Surprisingly, not only was Williams not selected for the role of Lupin, but he wasn't even given the opportunity to audition. Despite having previously worked with director Chris Columbus on 'Mrs Doubtfire', their prior collaboration did not factor into the decision-making process.

In a 2001 interview with the New York Post, Robin Williams openly discussed his feelings about missing the opportunity to star in the 'Harry Potter' films, mentioning that there were a couple of roles he would have been interested in playing. He humorously speculated about the possibility of joining the franchise in the future, saying, "Maybe one day. Say if [Harry] goes to Yale and becomes president" then he might have had a chance to be a part of the magical world across the pond. Despite missing out on the 'Harry Potter' series, Williams kept his sense of humor about the situation.