Actor Tom Welling (L) and director Peter Landesman (R) pose during a photocall for their movie "Parkland" at the 70th Venice Film Festival in Venice September 1, 2013.[Photo/Agencies]

US President John F Kennedy's assassination 50 years ago this year in Dallas is re-created in graphic detail, with a blood-smeared operating room and the famous film showing the actual event, in "Parkland" which had its premiere on Sunday in Venice.

"What a shitty place to die," an aide to Kennedy says in the film named for the Dallas hospital where Kennedy was treated and died on the operating table.

Zac Efron, former teen hearthrob from the "High School Musical" films, plays Dr. Charles Carrico, who started the emergency treatment of JFK. Paul Giamatti is Abraham Zapruder, the women's clothing manufacturer who happened to film the assassination with his home movie camera.

The operating room where nurses and doctors struggle to save Kennedy while surrounded by frantic presidential aides and secret service agents is awash in blood touching everyone in a "very Shakespearean" way, director Peter Landesman said.

Landesman, a former journalist, said he wanted to show what happened to the doctors, nurses, secret service agents, police and everyday people like Zapruder who were there on November 22, 1963 for an event that changed their lives forever.

"The assassination of Kennedy had been understood from the level of speculation and mythology and politics and ideas of conspiracy and something unknown happening in the ether that may have coalesced to kill him," Landesman said at a post-screening press conference.

"What we never really thought about was disorientation and the power and the chaos and the anarchy of what it was to seriously survive the assassination and that entire weekend."

Conspiracy theories, which have been rampant since the assassination, do not figure in "Parkland", Landesman said.

"For 50 years...the conspiracy speculation mythology has occupied a lot of emotion and intellectual real estate. That's there, that conversation is being had and always being had, it will never end. Our focus was really on the emotions, truths and survival."