Beck and St. Vincent also graced the stage at Tuesday's show.
Taylor Swift continued rocking the Staples Center on Tuesday night, entertaining the sold-out crowd with a few more of her famous friends for the fourth of her five L.A. shows.
St. Vincent and fellow Kanye West interuptee Beck were the singer’s first surprise guests of the night. The indie rockers joined Swift for a pyro-packed performance of "Dreams," the new song from Beck’s upcoming album.
Clip of Taylor, Beck and St Vincent on stage together! #1989TourLA pic.twitter.com/V1boJL15d7
— Hardcore Swiftie (@Swift13Updates) August 26, 2015WATCH: Taylor Swift's Second Night in L.A. Brings Surprise Guests Mary J. Blige & Uzo Aduba
Swift didn’t have any guests for her highly-anticipated "Style" catwalk, taking the stage solo and leaving fans wondering what surprises were still in store.
And she didn’t disappoint, introducing John Legend as the third surprise guest of the night. The singer, who was spotted in the crowd with wife Chrissy Teigen earlier in the night, joined Swift onstage to sing his hit ballad "All of Me."
The duet was totally spontaneous, Swift told the crowd, admitting, "I found out John and Chrissy were coming thirty minutes before I went on and called Chrissy and asked her if John would perform."
WATCH: Taylor Swift Kicks Off Her L.A. '1989' Tour Stop With Kobe Bryant, Ryan Tedder and More!
Swift also broke out some 1989 B-sides for the fans, and the sold-out crowd sang along enthusiastically to "Wonderland" and 'You Are in Love."
Several celebs were spotted in the audience, including Wil Wheaton, Mae Whitman, Brooklyn Decker, Derek Hough, and NBA star Russell Westbrook.
Achievement Unlocked: spotted a "No it's Becky" sign at the #1989TourLA.
— Wil Wheaton (@wilw) August 26, 2015WATCH: How Taylor Swift Is Headed for World Domination With Her '1989' Tour