And a face.

Weathered and worn by time, Robert Redford is our man. The only one you will see in this spare and unsparing film. A superhero in a hoodie and sneakers in the unlikeliest of action adventures.

The mission impossible is not to save the world, but himself. And the emotional crosscurrents we see on it become the film's narrative anchor.

The plot, by writer-director J.C. Chandor, is deceptively simple, yet marked by great philosophical and physical complexity. A sailboat somewhere in the Indian Ocean and a lost shipping container collide, leaving our man stranded on a sinking ship, a gaping hole in the hull, the transmitter fried. There is no one to talk to, and — more significantly — no reason to.

Though there is uncertainty in every moment of the eight days that our man's fate hangs in the balance, there is never any confusion about what is going on. All the existential questions are there in the doubt and the decisions.

In more concrete terms, the rare word that catches the eye — "lifeboat" on the side of the yellow-rubber inflatable — is unnecessary. We know. And the sailboat's name, Virginia Jean, works better as a mystery. Lover? Mother? Child? No matter, like so much else, when survival is in question.

"All Is Lost," which is only Chandor's second film, reveals itself as remarkably skillful, surprisingly insightful and deeply moving. It's a confident work by an artist who knows himself and trusts his audience. And it's a 180-degree turn from his first, the 2011 Wall Street hit "Margin Call." That fast-paced, slick corporate thriller was jammed with smart dialogue and earned the new filmmaker an Oscar nomination for original screenplay. It dealt with hubris.

Hope, humility and sheer determination shape "All Is Lost."

The canvas is a vast ocean, beautifully and simply shot. Director of photography Frank G. DeMarco handled everything above sea level and underwater cinematographer Peter Zuccarini the rest. There are no villains per se, though the laws of nature are a formidable adversary.

On the technology front, "All Is Lost," with its 2-D and micro-budget, is the anti-"Gravity" or half-"Life of Pi." Virtually no special effects are used; even the sharks that circle Redford are real. It makes for rough patches here and there that a few more dollars would have helped.

You don't have to be a nervous studio executive to know it is a huge risk to hang an entire movie on a script with almost no dialogue and a single, brutally physical role for one actor edging toward 80. But Chandor has turned these limitations into virtues. Starting with Redford.

The actor has always had a way of drawing the eye. There is an openness that suggests he can be trusted, a twinkle in those sky-blue eyes that hint at a tease, a smile that is just warm enough and tentative enough to temper the fact that he is incredibly, ruggedly handsome. Still.

It's also such a familiar face. One that has made so many characters indelible in major films like"Butch Cassidy and the Sundance Kid," "All the President's Men," "The Sting" and on it goes. Perhaps "The Natural" reflects his charisma best — Redford has always seemed a natural on screen. In "All Is Lost" he appears more at ease than ever. Stoicism and few words suit him.

In more recent times, Redford has struggled to replicate anything close to his early successes. In either small roles for someone else's movie, or a handful of earnest, relevant films — the most recent, last year's "The Company You Keep," in which he starred and directed — he hasn't managed to catch on at the box office.

Chandor, though, has given Redford the role of a second lifetime and the actor has delivered a star performance in return. Not showy, not melodramatic, but real.

The actor is 77 now, and he looks it on screen. At close range, the camera is as unforgiving as that ocean, every crease exposed. As much as the film is about a man lost at sea, it is also very specifically about an older man. The filmmaker isn't shy about showing his limitations, and the actor is astute in emphasizing that limits do not spell weakness.

Except for a few scary moments in the drink, this is a very intimate film. The action takes place on or below the deck of a 39-foot yacht, or a considerably smaller lifeboat with the lens inches away.

Though there is much drama in the various calamities that come along — a massive storm, the lack of food and water, a cut on the head just for starters — one of the sheer pleasures of the film is simply watching someone who knows what they're doing do. We've gotten in the habit of paying someone else to handle everything from our gutters to our psyches; seeing some can-do self-sufficiency is frankly inspiring.

Both the man and the sea are wily and unpredictable, eloquent in their silence, fierce in their resolve. It makes for riveting watching. You can almost smell the brine.

betsy.sharkey@latimes.com