James Brolin makes his voice-over debut in the Netflix series “Sweet Tooth” that hits close to home in the age of COVID.

Executive produced by husband-and-wife team Robert Downey Jr. and Susan Downey, the post-apocalyptic tale features Brolin narrating.

Based on Jeff Lemire’s DC comic book series about a deadly virus that killed almost everyone and led to new babies becoming human-animal hybrids, the show focuses on Gus (Christian Convery), a young boy who’s equal parts human and deer. With society uncertain whether hybrids stemmed from or created the mysterious virus central to the event known as The Great Crumble, Gus and a nomadic man, Jepperd (Nonso Anozie), venture out to discover the truth about hybrids.

“You know what’s so wonderful right now is that the Downeys were able to do this in the middle of COVID so well,” Brolin, 80, said. “It’s just all so well done and loving and, you know, I keep wondering, if you’re under 13, there’s a few scary things. But it’s really about love of family and what family is actually to all of us.”

Filmed in largely COVID-free New Zealand, the prologue addresses the fear-laden Great Crumble, a peculiar disease ushering in global change — an eerily familiar theme to watch, and for Brolin to record.

“I would just see bits and pieces (of footage), so it’s even more scary,” the “Amityville Horror” star said of the parallel. “I couldn’t really attach myself to anybody. … And I’m commenting on this pandemic, and meanwhile, we’re in a pandemic.”

The limited comic book series debuted in the latter half of 2009 and concluded in early 2013. It was followed by a sequel, “The Return,” first published in November.

Among the footage Brolin was shown were shots of “panic in the streets” that, Brolin agreed, felt a little prescient. The show, however, isn’t quite as dark as the comic.

“When we talked to Jeff Lemire, we talked about all the things we loved about the comic book, which was Gus and what he represented and his coming-of-age and sense of hope,” Susan Downey told Entertainment Weekly.

Brolin credits the Downeys with getting him on board, along with largely “sitting home a year” while the entertainment industry and his projects remained in flux.

The “Marcus Welby, M.D.” star had lunch with the couple, who also executive produced last year’s “Perry Mason” reboot. Things took off from there.

“The next thing I knew, they called and said, ‘We want you to narrate this.’ And I went, ‘Whatever you guys say. Whatever you want me to do, I’ll do,’” Brolin recalled.

Brolin recorded the entirety of his role from the comforts of home, which might be one upside to the past year.

The “My Brother’s War” director is optimistic about a second season, and his involvement.

“Well, the Downeys think so, and I see no reason. I mean, I’m just lucky to be around here at this age, you know?” he said. “And I do everything I can to — well, my mother lived to 100, so, you know, as far as I’m concerned, I’m tough as nails for my age.”