Sam Smith surprised fans at the Castro Theatre in San Francisco with a special guest appearance by rising pop singer Sienna Spiro during their “To Be Free: San Francisco” residency. The intimate performance took place at the historic Castro Theatre, one of the city’s most iconic venues and a landmark of San Francisco’s LGBTQ+ cultural community, which recently reopened after a two-year renovation.
During the show, Smith invited Sienna Spiro onstage for a powerful duet of her breakout hit “Die On This Hill.” The emotional performance quickly became one of the standout moments of the evening, blending Spiro’s soaring vocals with Smith’s signature soulful delivery in the theater’s intimate setting.
The collaboration marked a full-circle moment for the two artists. In late 2025, Spiro opened several dates of Smith’s “To Be Free: New York City” residency, where the pair performed a duet of Smith’s classic ballad “Lay Me Down.” Their reunion onstage in San Francisco highlighted Spiro’s rapidly growing profile as one of pop’s most promising new voices.
At just 20 years old, Sienna Spiro has built a global audience through her powerful vocal performances and emotionally rich songwriting. Her breakout single “Die On This Hill” has become a major streaming success, earning hundreds of millions of global streams and charting internationally.
Spiro recently launched “The Visitor Tour,” her first North American headlining tour. The run opened at the legendary Troubadour in Los Angeles and continues across major U.S. cities before concluding with two nights at Bowery Ballroom in New York City on March 17 and March 18. Her new single “The Visitor” arrives March 13 via Capitol Records.
Smith’s “To Be Free” residency series offers fans a rare opportunity to experience the artist performing in intimate venues rather than arenas. The San Francisco residency follows the success of the “To Be Free: New York City” run and coincides with the release of Smith’s recent single “To Be Free,” a stripped-down acoustic track exploring vulnerability, freedom, and emotional connection.
For fans at the Castro Theatre in San Francisco, the unexpected duet between Sam Smith and Sienna Spiro delivered a memorable moment that celebrated live music, collaboration, and the return of one of the city’s most beloved venues.
Featured image credit: Capital Records
