Vince Gilligan was "sure" Bob Odenkirk "wasn't going to make it" after he suffered a heart attack while filming 'Better Call Saul'.
The 59-year-old actor collapsed last July while filming scenes for the season six, part two premiere of the drama and the showrunner has recalled the "terrible" moment when his friend collapsed and "died right in front" of him.
Vince told BBC Culture: "It was just terrible.
"I've learned since that most people survive a heart attack. He had full-on cardiac arrest, which most people do not survive. It was awful. He died right in front of us."
Vince praised the quick actions of various people on set, including the emergency medical technician on duty, for saving Bob's life while he stood by "completely useless".
He added: "They saved his life right in front of me. I'm standing there like an idiot. I don't know what to do. Just completely useless… We were sure he wasn't going to make it.
"We didn't even know at that point if we were ever going to finish the show or not, but knowing he was going to survive helped an awful lot. Those were some very dark days."
After being hospitalised, Bob returned to set a few weeks later to complete the scene he had been midway through shooting when he collapsed.
Vince said: "It’s a very dramatic scene near the beginning of the episode. Two thirds of it was shot before he had a cardiac arrest, a third of it after. I defy you to notice the difference."
Bob previously admitted those who were working the day of his heart attack were more "traumatised" by his medical emergency than he was.
He said: "I would say that the cast and crew were more traumatised than me, because I have a blank space where I had this heart attack.
"I don't remember the day it happened or the next week and a half. They all were standing right there. And they watched me go down, and they watched them use the defibrillator three times on me, and they watched the professionals around look at each other and say he's not coming back."
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