The crowd that gathered at Hyde Park in London for Barbra Streisand's set on Sunday (July 7) during British Summer Time got the ultimate surprise when she invited Kris Kristofferson to perform the duet "Lost Inside of You" from their hit 1976 remake of A Star Is Born. 

Bringing their characters Esther Hoffman and John Norman Howard to life with a rendition of the tender ballad, Streisand invited Kristofferson to the stage by referring to him as "one of my favorite leading men." The crowd erupted in cheers at Kristofferson's presence, the two icons holding hands throughout the performance as they sang to one another "When you came inside of my life / Now I'm lost inside of you / Lost in the music / And lost in your eyes."

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Streisand co-wrote "Lost Inside of You" for the film alongside the late Leon Russell. Streisand and Kristofferson's adaption of A Star is Born went on to win five Golden Globe Awards in 1977 including Best Motion Picture - Musical or Comedy, while both leading stars picked up wins for Best Actress and Best Actor for Motion Picture Musical or Comedy. The film's shining number "Evergreen" was named Best Original Song at the 1976 Academy Awards, co-penned by Streisand and Paul Williams.

Lady Gaga would later go on to win this same award for "Shallow" in the wildly popular 2018 remake of A Star is Born where she plays the role of Ally Campano alongside Bradley Cooper's Jackson Maine. The Hollywood pair called on a team of Nashville songwriters to help create the film's soundtrack including Jason Isbell, Lukas Nelson, Lori McKenna, Natalie Hemby and Hillary Lindsey.

See the Top 50 Country Duets of All Time!

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