Taylor Swift wrapped up her star-studded 1989 tour in St. Louis last night, and naturally, she brought out Nelly to perform his classic hit, "Hot in Herre," with the assist from her and HAIM​. Nelly is just one of the many guests that Taylor brought out on stage during the lengthy tour, but this performance might have taken the cake, as the crowd went absolutely crazy throughout the duration of the song, and especially wild when Taylor and HAIM dropped in some timely adlibs. See all the craziness unfold below.