Fans of "A Star Is Born" got a special treat Saturday night at Lady Gaga's show in Las Vegas.
According to Variety, Gaga brought Bradley Cooper, her co-star from the Oscar-nominated film, onstage at the Park Theater for a live performance of their hit song, "Shallow."
Fans cheered as the pair sang the duet, an Academy Award nominee for best original song. Cooper and Gaga also were nominated in the best lead actor and actress categories, respectively.
>> Click here to watch the performance
