Mariska Hargitay's Most Unforgettable Guest Star On Law & Order: SVU

With over a quarter-century of episodes, "Law & Order: SVU" has been host to a number of amazing guest stars. But to Mariska Hargitay, one special guest blew everyone out of the water, telling Variety that when the legend came in, "We had so much fun, and there was so much joy. He was such a light." That icon, who is remembered by all for his sense of humor and unforgettable laugh, was none other than Robin Williams.

Williams made his appearance in the show's Season 9 episode "Authority," playing a man who tricks strangers into committing crimes as a way to get revenge following the tragic death of his wife. Williams' work in the episode earned him an Emmy nomination and has gone down as one of the best episodes of the long-running series. The episode was one of the most dangerous for Detective Olivia Benson, who is held captive by Williams' character, but for Hargitay, seeing Williams work was magical. She explained to Vanity Fair in 2024, "To watch somebody in utter flow, to watch flow happening; that which is invisible, he was the personification of it. It was magnificent."

But the moment Hargitay, the daughter of Jayne Mansfield, will never forget was seeing Williams interact with her son, bringing her to the verge of tears as she described the moment. "Robin grabbed him and picked him up, and was so kind and doing voices for him. And you're just in this moment going, 'I'm pinching myself that I get to live in the same time with somebody so magnetic, and so magic, and so generous." Not surprisingly, this is just one of the many stories about how wonderful Williams was.

Best known for his comedic roles, Robin Williams was just as talented at drama, most notably starring in "Good Will Hunting," which earned him an Academy Award. In his dramatic films, Williams usually played a good person looking to be there for others. The first time he was able to really show the world his darker side was in Christopher Nolan's 2002 film "Insomnia," where he played a killer. But his role on "Law & Order: Special Victims Unit" really showed viewers how terrifying he could be. 

Williams took the role as a favor to an old friend, "SVU" co-star Richard Belzer. Belzer and Williams were comedians in the 1970s and, according to Neal Baer, who wrote the episode Williams is in, "Richard Belzer also made it possible for us to have Jerry Lewis and Robin Williams on SVU. He reached out to them for me and ... they were incredible." But that wasn't the first time Belzer's friend showed up to help one of his shows out.

Before "SVU," Belzer played the same character, Detective John Munch, on the critically acclaimed but low-rated "Homicide: Life on the Street." The series was on the verge of cancellation when producer Barry Levinson, who worked with Williams on "Good Morning, Vietnam," asked the actor to guest star. With Williams' appearance, "Homicide" suddenly saw its ratings rise, ensuring it would run for years. That episode was also the first episode of TV that David Simon, the creator of "The Wire," ever wrote. Simon credited Williams for saving his career, saying on his blog that without Williams, "I'd be on a newspaper copy desk somewhere."