As she performed the chart-topper, Swift made good on her promise of "some surprises" as she introduced model friends Martha Hunt and Gigi Hadid. A Victoria's Secret Angel, Hunt was also among the singer's femme fatales featured in the "Bad Blood" video, where she played "HomeSlice." Hadid, a Sports Illustrated model, starred in the video as "Slay-Z."
As for the Michigan stop during Swift's massive 1989 World Tour -- which runs through December (so far!) -- Hunt and Hadid weren't the only night's shockers. Imagine Dragons lead singer Dan Reynolds joined Swift for a blazing rendition of the band's hit "Radioactive."
Want more of Taylor and her gal pals? Here they are looking fierce: