Taylor Swift

Taylor Swift and Calvin Harris locked eyes during a concert in Los Angeles Monday, prompting the "Bad Blood" singer to mouth the words "I love you" on stage.

Harris, 31, stood in the crowd at Swift's sold-out concert, close to the end of the catwalk stage on which Taylor finished her show. After taking a few bows and courtesies, Swift stopped to mouth the lovey-dovey line in Harris' direction.