The tens of thousands of people who flooded New York City's streets on Saturday to protest gun violence included a very famous face: Sir Paul McCartney.
The former Beatle explained why he felt compelled to join the March For Our Lives, a student-led march against gun violence and school shootings.
"One of my best friends was killed in gun violence right around here," McCartney told CNN, "so it's important to me."
Fellow Beatle John Lennon was shot to death in 1980 outside his apartment, just steps away from where McCartney marched.
