HAIM had a special guest during their London concert and it was none other than Taylor Swift. The singer hit the stage to perform a mashup of “Love Story,” and “Gasoline.” Swift even gave fans a monologue between songs. Swift, who wore a matching all-black Louis Vuitton outfit. During her monologue, Swift addressed how big the audience was, 20,000 people to be exact. Some Swifties think Taylor’s performance was a hint of things to come as she belted out “Bad Blood,” which will be featured in the upcoming in DC League of Super-Pets. Do you think Taylor is getting ready to release “Bad Blood (Taylor’s Version)”?