It’s not always easy to tell whether the new documentary titled The Immortalists is sympathetic to its two primary characters or whether it’s making fun of them. The men in question, Bill Andrews and Aubrey de Grey, are scientists who have independently vowed to cure aging and vanquish death. That alone suggests they belong in the fruitcake bin, along with the better known Ray Kurzweil, who intends to have his brain uploaded to a computer in 2045 in an event he calls the Singularity.

The impression becomes stronger when directors David Alvarado and Jason Sussberg delve into Andrews’ and de Grey’s lives and backgrounds, in an attempt to help viewers understand what motivates them. The bottom line: they disapprove of death. “This wasn’t supposed to happen,” says a tearful Andrews at one point of a colleague who died of cancer at a relatively young age. “We were on the same mission.” Biology evidently hadn’t gotten the memo. De Gray, meanwhile, walking through a cemetery, declares, “I don’t want to get Alzheimer’s and end up in a place like this.”

Most of us agree that death seems unfair, unless we believe in a redemptive afterlife, which neither Andrews nor de Grey seems to—and even religious folks would generally like a few more decades of life before going to the Great Beyond. Most of us also believe bad things shouldn’t happen to good people—a sort of “All I Really Need to Know I Learned in Kindergarten” philosophy that’s as appealing as it is unanchored in any sort of rationality.

Both Andrews and de Gray are scientists, though, and their parallel quests to defeat aging have at least a plausible scientific basis. The key, they believe, lies with the telomere, a sort of protective endcap on our chromosomes that shortens every time a cell divides. When the telomere gets too short, the cell’s number is up. But a natural enzyme called telomerase can protect the telomere from damage, which suggests that having more of the enzyme could stave off aging and death.

So far so good, and scientists worldwide are looking into the details of exactly what telomerase does and how it does it—and whether boosting it artificially might help stave off aging. Those details could prove to be devilish, though. Back in the late ’70s scientists were intrigued with a natural substance called interferon, which showed promise as a magic bullet against cancer. It wasn’t. In the late ’90s there was lots of excitement about anti-angiogenesis drugs, also meant to wipe out cancer. But despite early promise, they too have failed to impress.

Most scientists are more careful now about making dramatic pronouncements about magic cures even for single diseases, let alone aging and death itself. But not Andrews or deGray. As it happens, legitimate, independent scientists are few and far between in The Immortalists, and those who do appear are less than effusive. “I find Aubrey’s position quite difficult to pin down,” says Colin Blakemore, a neuroscientist at the University of London. “He made a statement that the first person who will live to 1,000 is alive today. I think that’s foolish.” William Bains, meanwhile, a biotech entrepreneur admires de Gray for being able to drink prodigious amounts of alcohol and still think serious scientific thoughts. I’d take an anti-aging cure created by a guy like that. Wouldn’t you?

The directors want us to understand both de Gray and Andrews as visionaries whose own private lives exemplify their maverick attitudes toward conventional wisdom. That part certainly works: we see Andrews running a 100-mile-plus ultramarathon across the Himalayas and we get to watch de Gray frolic nude on a blanket with his wife. (de Gray is polyamorous; his wife is not amused).

The film itself, which premiered last week in New York and opens December 11 in Los Angeles, artfully leaves it up to viewers whether de Gray and Andrews are crackpots or whether they’re outside-of-the-box thinkers who truly might help us live forever.

My vote: they should have stayed in the box.

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