This wasn't the first time the two have teamed up. Back in November, James played with Taylor at Madison Square Garden, and while that one was a surprise, the Massachusetts collaboration was an open secret. Hence the outpuring of young fans, among them Lucie Mazursky, an 8-year-old Swift superfan who gushed to the Berkshire Eagle about how excited she was to see the concert.
"I almost fainted," Lucie said, adding, "I only have her songs on my iPod."
Watch Taylor Swift's 'Eyes Open' Lyric Video