What's one celebrity impression when you can do 29 in less than four minutes — while singing, no less? That's exactly what singer-songwriter Rob Cantor seemed to do in his viral video, but in a behind-the-scenes clip released later, we learn the truth: Rob had the help of 11 impressionists. As for Rob, he admitted, "I cannot do a single celebrity impression." To create the viral video, the impressionists recorded themselves singing Rob's original song called "Perfect," with the group covering everyone from Britney Spears [1] to Adam Sandler [2] to Gwen Stefani [3]. Watch his lip-sync performance in the original video above, then watch the making of the video below.