Jeremy Renner says he wrote 'last words' to his family while hospitalized after accident in new Diane Sawyer interview

Jeremy Renner's new interview with Diane Sawyer is going to be an emotional one.

The Avengers actor sat down with the veteran journalist to talk about his recovery from the brutal accident that occurred on New Year's Day, when he was run over by a snowplow, after he tried to stop the machine from hitting his nephew.

In a preview of the conversation that aired Wednesday on Good Morning America, Renner choked up as he talked about the moments after he was pulled under the 14,330-pound snowplow.

"If I was there on my own, that would have been a horrible way to die," he told Sawyer. "And surely it would've. Surely. But I wasn't alone. It was my nephew, sweet Alex, and the rest of the cavalry came."

Renner also explained that he understood the gravity of what had happened to him.

"So I'm writing down notes on my phone," he said, "the last words to my family."

In the full trailer, which was released March 29, Renner's nephew was upset, too, as he talked about the traumatic event.

"I just perfectly see him, in a pool of blood coming from his head," the nephew said. "I ran up to him, and, you know, I didn't think he was alive."

Renner was alive, but he had broken more than 30 bones. Recovery has been exceedingly difficult.

The star of the upcoming Disney+ series Rennervations has shared looks at his grueling physical therapy sessions, which include walking on an anti-gravity treadmill, on social media.

Still, in the new footage, Renner explained to Sawyer that he'd "do it again."

"You'd do it again?" she asked.

"Yeah," he answered, "cause it was going right at my nephew."

Renner's interview airs Thursday, April 6 at 10 p.m. on ABC.