That day and the way it affected different Americans' lives is being revisited in the film written and directed by Emilio Estevez called, simply, "Bobby."
"It was as if someone had pulled the rug out from underneath our entire generation," Estevez said. "And I believe the generation went into freefall after that. I think that the death of Bobby Kennedy was in many ways the death of decency in America. It's a very important day in the history of American politics and in our history in general."
In his film, Estevez intercuts actual pictures from that time with the stories of 22 fictional characters whom he places at the Ambassador that June day, a cross-section of America dealing with issues of prejudice and politics, of drugs and the draft.
The cast includes too many big names to fit on one marquee: Demi Moore, Lindsay Lohan, Heather Graham, Helen Hunt, Laurence Fishburne and Estevez's father, Martin Sheen.
Sheen took Emilio to the Ambassador just one year after the assassination when he was seven years old.
"I remember holding my father's hand and walking through the lobby and walking through the Embassy Ballroom, and I remember my father saying, 'This is where it happened. This is where the music died,'" Estevez said.
Robert Kennedy was his brother President John F. Kennedy's closest advisor. He managed his presidential campaign, and became his Attorney General. There was a side of RFK that could be tough and aggressive, but Estevez doesn't show that in the new film.
"Well, you know, had it been a biopic, had I had more time. This was about that day," Estevez said.
In fact, by the time of his death, Robert Kennedy had undergone a transformation.
"The hard-boiled political operative of 1961, say, to 1964, changes," presidential historian Douglas Brinkley said. "It becomes from '65 to '68 the champion of the underdog. The myth of Robert Kennedy and the emotional aspect of his persona [is] the man who dared to care about the poor and the forgotten people. Bobby Kennedy entered the other America — people of barrios, people of ghettos — and was embraced by them. And that's the Robert Kennedy that gets celebrated."
Singer and civil rights activist Harry Belafonte helped educate Robert Kennedy to the issues facing black Americans, and served as a link between Dr. Martin Luther King Jr. and the Kennedys. For him, being a part of this film was a chance to pay tribute to his old friend Bobby.
"It's an important part of America, the soul of this nation," he said. "For his voice to be heard as powerfully as it's heard in this film, I think is a great gift."
Belafonte and most of the rest of the cast were on hand when "Bobby" opened the AFI Film Festival earlier this month.
"I was a little star-struck," Estevez said. "It was overwhelming. It was very humbling, to go from where I'd been in the last decade, which is relative obscurity."
Estevez was once a member of Hollywood's Brat Pack in such films as "St. Elmo's Fire" and "The Breakfast Club." His star was fading in the late '90s, even as he branched into writing and directing.
"I was at a point where I was having to redefine myself," he said. "I was not in a good place, spiritually. I was not in a good place emotionally. I was kind of floundering. I had done one too many "Mighty Duck" sequels and Hollywood really wasn't that interested any more in what I had to say or what I had to offer."
In 2000, he was on a photo shoot in the then-shuttered Ambassador Hotel and saw where Kennedy was shot.
"It was behind these padlocked doors," Estevez said. "They opened the doors and it was like standing on hallowed ground, truly. It just took your breath away. That was the moment where I thought, why hasn't anybody made this film? Why hasn't anybody told this story?"
Estevez and Academy Award-winning editor Richard Chew were still tweaking the film two weeks before this Friday's opening. But it was a movie that began on a shoestring budget. Estevez said the initial budget was just about $5.5 million.
Sharon Stone, like the rest of the cast, worked for the Hollywood minimum for a chance to be a part of "Bobby."
"If you understand fame, you have to understand that you have to spend that like currency," Stone said. "If you're gonna spend it, you better spend it on something of value."
In fact, for just about everyone associated with the movie, "Bobby" seems to be more a labor of love than just a movie. Estevez said he has received encouragement from the Kennedy family.
"They're endorsing the movie because they believe that this is a new generation that's going to hear Bobby Kennedy's words all over again, at a time when perhaps we need him more than ever," he said.