— -- Taylor Swift has made her 1989 a star-studded affair.
For weeks, the "Bad Blood" singer has invited celebrities to join her on stage, but since coming to L.A. for a series of shows, she's turned things up a notch.
During her shows at the Staples Center, St. Vincent, Beck, John Legend, Alanis Morissette, Natalie Maines, Ellen DeGeneres, Uzo Aduba, model Sean O'Pry, Chris Rock, Matt LeBlanc, Mary J. Blige, Ryan Tedder, and Kobe Bryant have all made appearances during her shows.
"I don't know how to process any of the events of tonight," she wrote of last night's concert.
All across the country, however, other stars have joined Swift, 25, for some of her biggest songs (and, in the case of some musicians, a few of theirs!), too.
Among them: Julia Roberts, Joan Baez, Fifth Harmony, Little Mix, Ciara, Russell Wilson, Fetty Wap, We Are MKTO, Walk the Moon, Sam Hunt, Andreja Pejic, Lily Donaldson, Andy Grammer, Serayah, Jason Derulo, Lorde, Candice Swanepoel, Lily Aldridge, Martha Hunt, Karlie Kloss, Behati Prinsloo, Gigi Hadid, Nick Jonas, Hailee Steinfeld, Lena Dunham, the U.S. women's soccer team, the Weeknd, Sophie Turner, Mariska Hargitay, Cara Delevingne, Echosmith, Rachel Platten, Imagine Dragons, and Little Big Town.