Alec Baldwin explains how the gun fired on 'Rust' set without him pulling the trigger

In an exclusive interview with ABC News anchor George Stephanopoulos airing Thursday, Alec Baldwin sat down to discuss the tragic shooting on the set of the film Rust in October. While rehearsing a scene, Baldwin allegedly discharged a prop gun containing live ammunition. The bullet struck and killed cinematographer Halyna Hutchins and injured director Joel Souza.

Baldwin was rehearsing a scene in which he was to draw his gun and cock the hammer. He claims Hutchins directed him where to point the gun so that she could get the best shot.

“[I pulled] the hammer as far back as I could without cocking the actual gun,” Baldwin explained. “I'm just showing [it]. I go, ‘How about that? Does that work? You see that? Do you see that?’ And then she goes, ‘Yeah, that's good.’ I let go of the hammer, bang! The gun goes off.”

Baldwin claims he had no idea that the gun contained a live round. The gun was not supposed to contain a blank round, but that was his initial thought. He believed that perhaps wadding, which is occasionally put in prop guns containing blanks, came out and hit Hutchins.

“She goes down,” Baldwin said. “I thought to myself, ‘Did she faint?’ The notion that there was a live round in that gun did not dawn on me till probably 45 minutes to an hour later.”

The set was immediately evacuated to allow medical staff and first responders to treat the victims. Baldwin claimed that no one on set realized an actual bullet had struck Hutchins and Souza until a sheriff's deputy showed them a picture on his phone.

“No one had any idea until that sheriff's officer said to me, ‘This is the slug. .45 caliber slug they took out of Joel's arm,’” Baldwin recalled. “And then the kind of insanity-inducing agony of thinking that someone put a live bullet in the gun.”

The investigation is ongoing and Baldwin claims he is cooperating with officials but doesn’t believe he’ll be criminially charged. Two Rust crew members have already filed civil suits against the production company and Baldwin personally. Baldwin did say he fully understands and expects Hutchins’s widow to file a suit.

“I would go to any lengths to undo what happened,” said an emotional Baldwin. “I would go to any lengths to undo what happened.”

Alec Baldwin: Unscripted aired on ABC Thursday night at 8 p.m.

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