Isabel Leonard (b. 1982) is mezzo-soprano opera singer, having graduated from the Julliard School and doing various performances at Lincoln Center.
She appeared in the season 43 finale of Sesame Street in Murray Monster's "People in Your Neighborhood" segment. She explains what an opera is to Murray and Ovejita and allows him to sing a little in a short performance of the aria "Una voce poco fa" from The Barber of Seville.
In a 2019 interview with Vogue, Leonard recalled how the guest spot came about:
“I was working at Glyndebourne, in England, when I got a call from a publicist I worked with saying that Sesame Street wanted someone for a segment called “These Are the People in Your Neighborhood.” “But it sounds like you’re just too far away to make it happen,” he said. And I said, “Absolutely not—I’ll be there right away!” I got a release from the production I was working on for a couple days, flew back to New York, did the filming the next day, and hopped back on a plane to Glyndebourne. There was no way I was going to miss that opportunity.”