>> former beatle john lennon was gunned down in front of his exclusive manhattan apartment -- >> the life of a folk hero -- >> gunned down as he entered -- >> the news ripped through the air in shockwaves. john lennon shot and killed in the dakota apartment building -- >> it was really shocking. 40 years old, john lennon of the beatles. how could he be dead? how could this have happened? the city was in shock, not just people of my generation that grew up listening to their music in the '60s. i think just about everybody felt that, on so many levels, it was wrong. >> it was terrible. i mean, i think just the way so many people that didn't even know john felt -- it just hit home with me much more because he befriended me, and he didn't have to befriend me. >> in new york, cnn investigative reporter laura dedio has come up with new facts about john lennon's accused killer.