Justin Bieber suprise Taylor Swift on a Concert in Los Angeles

Taylor Swift’s concert at LA’s Staples Center — the one and only Justin Bieber.

The audience reacted with squeals of delight when Swift brought her mega-star friend on stage to perform a duet of his hit song, “Baby,” with her.

And the crowd went wild.

Their song choice doesn’t come as a surprise, however. According to Billboard, Swift covered Bieber’s “Baby” during her shows in Montreal and Toronto in July.