The set – which thematically matched the super sci-fi/cyberpunk music video she released for the single last month – marked the first time she's performed the track live in public.
In her second set of the night, singing the fourth single off the new album, "Call It What You Want," Swift brought things down to earth for an emotional, personal performance in which she sat in a chair and played her guitar.
For the track – which simultaneously disses some of her enemies and boasts about her happy life with her new man – Swift rocked a black sweatshirt which what appeared to be planets and constellations, along with a large red snake emblazoned across the front.
This was Swift's third time serving as music guest on the sketch comedy series. She first performed in 2009 in an episode hosted by Neil Patrick Harris, then returned later that year, during the next season, as both the musical guest and the show's host.
While Swift's SNL performance of "…Ready For It?" was pretty spectacular, the music video was next-level epic. In the CGI-heavy video, Swift plays both an evil robot and her own nearly naked robot clone, who have to battle to the death in a Blade Runner-esque abandoned mall.