There is no way to describe All Is Lost and end up making it sound like it's broadly accessible, which is really too damn bad. For it truly is one of the films of 2013 I'd feel best about recommending to the largest number of people for the most diverse set of reasons, virtually complete absence of dialogue and all. It's certainly one of the year's most unusual movies and interesting to discuss. That it is also one of the year's best movies does not entirely follow, though I think that argument can be made.

The film opens with a man in his late 60s, played by Robert Redford, waking up to find that his sailboat has been struck by an errant cargo container full of sweatshop tennis shoes, and he is taking on water. We do not know what he was doing alone on a ship, out of sight of land; we do not know who he is in his daily life, if he owned that ship and was rich, or where the money came from if so. We don't know his name - he's identified as "Our Man" in the end credits. He has, effectively, no identity, and in the time we spend with him, he is totally reactive: the entirety of the 106-minute film consists of him solving one problem that threatens to immediately plunge him into the depths of the ocean, taking barely any time to rest, and discovering that there's another problem of equal or greater severity. As will happen, of course, when one is alone in a sinking boat in the middle of the ocean.

J.C. Chandor's second film as writer and director is just about as far removed from his first, the 2011 financial thriller Margin Call, as it is possible to get - one actor instead of a jam-packed ensemble, virtually no dialogue instead of constant talking, purposeful vagueness instead of pushy roman Γ  clef symbolism. And while I thoroughly enjoyed that film, the shift entirely favors All Is Lost, which is just as taut a piece of genre filmmaking while exploring a much trickier genre from a much more radical position. All Is Lost is the latest in the trend of "isolated people stuck in one place wondering if they're going to die" films that stretches from at least Open Water all the way up to Gravity, though it does something that none of those films have had the balls to do, following through on its concept all the way to the bitter end. This is a film about being well and truly isolated, not "alone but with radio contact with Houston, some guy in Asia, and hallucinations of a colleague", nor "alone but with a cellphone that permits nearly constant conversation", as in Buried from a few years back. Our man is completely alone for an entire feature film, interrupted by only two moments when he doesn't come even close to flagging down big cargo ships with his thin shouting and single flare.

This has interesting ramifications both for the performer and the film, though in fairness, All Is Lost is a film such that there's really no drawing a line between the two. Indeed, one of the most fascinating things about it is how Chandor uses Redford, more as a meat puppet than as an actor playing a human. Since the film is in large part an opportunity to watch in detail as a man in an extreme situation attempts to resolve his situation, Redford's performance is almost exclusively physical, interspersed with a few piercing reaction shots when he has an opportunity to catch his breath (and those reactive emotions are some of the best acting Redford has ever done, mind you, so I'm certainly not trying to say that this is just mechanical non-acting). Putting a hugely recognisable and canonically gorgeous movie star in that role was essential to the movie's effect: instead of just watching a human being like you or I stuck in a miserable place, getting more miserable, Chandor is thus able to make it about someone larger-than-life, someone notable inhuman, which increases the dreadfulness of it all: if even someone rich, handsome, and famous has absolutely no recourse in this situation, what chance do the rest of us have?

What emerges isn't a commentary on movie stardom so much as an exercise in using movie stardom to deepen the context of the story (Redford is awfully good, but I think the film would tend work more or less the same with any equally famous movie star of his age bracket; not that there are too many of those, mind you) All Is Lost is, first and above all, a story of the human survival instinct, stripped to its most basic iteration: if this man stops doing what he's doing, he'll drown, the end. That sounds completely awful, I know, but in the movie it is unbelievably gripping and thrilling for the whole time (106 minutes seemed, beforehand, like far too much time to spend with this scenario, but in the end I was shocked when it was over already), and it's only as symbolic and thematically resonant as you want it to be. Just need a thriller about one man fighting for his life for eight days, depicting with fascinated detail how he goes about doing that? It has you covered. Want to take it instead as a heavily symbolic tale of Everyman finding himself in a life that keeps getting worse no matter how much effort he puts into fixing it? It has you covered there, too, and you'll also probably get more out of the cryptic final scene if you prefer to take it that way.

Such a simple, direct story needs a lot of fine work to keep it afloat, and Chandor and his crew bring to bear some absolutely terrific work across the board, especially in the marvelous soundscape (there's a storm that has pretty much the best audio work of the year) and Peter Beaudreau's perfectly-timed cutting, which shaves every excess out of the movie and leaves it in a place of the finest, Hemingway-esque minimalism. We know only what we need to know, and we see only what we need to see, and that's enough to let the film barrel along mercilessly, letting neither us nor our man relax for even a moment. This is terrifically precise filmmaking that hits like a bag of hammers, and even if has very little "to say" about humanity, it has more feeling in it than plenty of films that want to telegraph more how much they're making us feel.