All Is Lost does not have much business being as captivating as it is. Director and writer J.C. Chandor (Margin Call) takes a concept that seems like it could only work in a short film and blows it out to feature length. With help from the great Robert Redford, he's mostly successful.

Redford plays the nameless hero, a man alone on a sailboat in the Indian Ocean who must fight for survival after a stray shipping container blasts a sizable hole in the hull of his vessel and consecutive storms further imperil him.

There is no one else in the film, and, after a voiceover at the very beginning that hints at the reason he's at sea all by his lonesome, Redford hardly utters another word. Even in the lone survivor sub-genre, Chandor removes any and all plot devices that might get his main character talking. There is no Wilson to make conversation with, no intermittent radio signal after the first few minutes to offer the possibility of human connection.

In this way, All Is Lost feels like a grand and challenging cinematic experiment that works because Chandor comes up with enough ways to signal what's going on without having Redford open his mouth. There is his use of an astrolabe and a nautical map to show us that he's drifting toward a shipping lane that offers him hope of being saved. There are his spit-takes as he realizes his container of fresh water has been contaminated. There are countless other moments where the desperation of Redford's character -- really almost every one of his movements -- screams out to the viewer, creating an atmosphere thick with tension. It's just a mostly wordless scream.

The parallels between All Is Lost and Best Picture nominee Gravity are obvious, right down to pieces of junk (sea or space variety notwithstanding) putting the respective hero and heroine in mortal danger. Though both films fixate on the human will to survive, the latter has a much more spiritual bent to it. Gravity cares to try to explain its protagonist's feelings of isolation -- to put her somewhere on the globe (even though she's ironically in outer space) and among humanity at large. All Is Lost does not do this, beyond Redford's opening declaration that, "I'm sorry. I know that means little at this point, but I am. I tried. I think you would all agree that I tried. To be true, to be strong, to be kind, to love, to be right. But I wasn't. All is lost."

I mention this not because I think one slant is better than the other but because thematically these are very different films despite their superficial similarities. All Is Lost hardly examines Redford's will to live at all. That force just is. All by itself that's interesting enough. But I'd classify it as interesting and impressive more than interesting and great. For some, this unquestioning chronicle of survival on offer here will work better. But for me, it leaves it just a little lacking what is required for greatness.