Then, 10 minutes in, comes word of a Russian satellite destruction exercise that's gone awry. A cloud of deadly debris is racing for them. And before they can abort the spacewalk, get inside the ship and get away, it is trashed, their third space walker is killed and they're stranded, with mere minutes of oxygen in Stone's suit standing between her and an even quicker death than the certain doom facing them both.

Clooney's soothing voice is used to wonderful effect as he calms the space rookie down. His Kowalski is Mr. "Right Stuff," coming up with a plan (jetting over to the International Space Station, which had to be abandoned because of the coming debris assault) and making Stone tell him chunks of her life story to still her panic.

Oxygen? "Sip, not gulp. Remember, wine, not beer."

The movie plays out in something like real time as they have 90 minutes before the next space junk pass to get to safety. But everything, and I do mean everything, stands in their way. The only missing menaces are Darth Vader and the creatures from "Aliens."

Bullock's Stone speaks for all of us as she deals with each fresh horror with a "What now?" She does some of her best acting in years, her mood shifting from desperation to resignation with just a look. She is well-cast as someone vulnerable, overmatched but with a backbone that surprises.

Cuaron, who directed "Children of Men" and the best Harry Potter movie ("Prisoner of Azkaban"), uses the silence of space brilliantly — muffled, distant radio transmissions, shockingly violent but silent crashes, with only the sound of panting and faint yelping (in Bullock's case) from our intrepid space explorers underscoring the disaster. They're hurled, yanked and thumped, and all we hear is their gasping, their crackling radios and a thunk if they hit compartment of a space ship that has oxygen in it.

The parade of accidents takes "Gravity" close to the realm of melodrama, and the physics of it all isn't flawless. But you'd have to go back to "Apollo 13" and such '60s epics as "2001: A Space Odyssey" and "Marooned" to find a film this determined to perfectly dramatize the very real perils of spaceflight.

Bullock and Clooney make their peril our peril in this absolutely gorgeous, moving and sometimes exultant reminder that the real terrors of space are scary enough, without throwing in invented bug-eyed monsters.