Jeremy Renner is opening up about his life-threatening accident involving his snowplow in his first interview since the incident with ABC News anchor Diane Sawyer.

In a first look for "Jeremy Renner: The Diane Sawyer Interview -- A Story of Terror, Survival and Triumph," airing Thursday, April 6, at 10 p.m. ET on ABC, the "Avengers" star reflects on the January accident involving his seven-ton snowcat.

"If I was there, on my own, that'd [have] been a horrible way to die. And surely I would've. Surely," Renner said. "But I wasn't alone. It was my nephew. Sweet Alex. And the rest of the cavalry came."

Renner, who says he suffered more than 30 broken bones as a result of the accident, along with blunt chest trauma, said he wrote a goodbye note to his family while in critical condition at the hospital.

"I'm writing down notes in my phone to -- last words to my family," he recalled, tearing up.

In a trailer released last week ahead of the forthcoming special, Renner said he remembers the pain from the accident.

"I was awake through every moment," he told Sawyer, but said that he would "do it again."

"Yeah, I'd do it again -- because it was going right at my nephew," he said.

The exclusive also features harrowing recollections of the accident from Renner's family members, including his nephew he was trying to protect, and behind-the-scenes snapshots from his ongoing journey to recovery.

He also told Sawyer that he "chose to survive" after the accident and refused to let it kill him.

When asked about his hope for the future when it comes to stunts that come with action-packed roles, Renner said, "I've lost a lot of flesh and bone in this experience, but I've been refueled and refilled with love and titanium."

Watch "Jeremy Renner: The Diane Sawyer Interview -- A Story of Terror, Survival and Triumph" on Thursday, April 6, on ABC and the next day on Hulu.