first time on the air in the united states, here are the beatles singing "i want to hold your hand." ♪ oh, yeah, i'll tell you something i think you'll understand ♪ >> that song really started to take off. it was impossible to anticipate how much that momentum would continue. ♪ i want to hold your hand ♪ >> hi, everybody all over america. this is the wabc party go go, whoo! ♪ i want to hold your hand ♪ >> that song was absolutely contagious, and i think the teenager found a voice. ♪ i can't hide ♪ >> here's what's happening, baby, the beatles! ♪ i can't hide ♪ ♪ yeah, you got that something ♪ >> there was a moment where you just heard, this is our music now. it was like hearing the future. ♪ i wanna hold your hand ♪ >> but i have to ask how you first found out about them. >> when i first heard about the beatles, it was at london