"Mastermind" is a song by American singer-songwriter Taylor Swift, released on October 21, 2022, as the final track on the standard edition of her tenth studio album, Midnights (2022). Written and produced by Swift and Jack Antonoff, the track has lyrics about a protagonist confessing to her lover that she in the past had carefully initiated a plan to make him love her. The production consists of swirling arpeggiators, layered vocal harmonies, and expansive bass. The track peaked within the top 20 in Australia, Canada, and the United States, and peaked at number 13 on the Billboard Global 200.