Gravity is just a theory, one of those soundbytes physicists like to brandish in order to explain the properties of energy and matter.

It’s also the title of a web of visual sorcery woven by director Alfonso Cuarón, whose two-person space odyssey Gravity took me completely by surprise. Prepared to submit to a few hours of special effects tedium, I was instead immediately mesmerized and in the end, deeply moved. And here at last was a film in which the use of 3D photography made gorgeous sense.

Gravity is a loveletter to our sweet, flawed, blue planet, an allegory told—as perhaps it only can be—from a long way away.  As two astronauts spin helplessly in a spacewalk gone wrong, the smooth majesty of earth’s oceans, land masses and great graceful clouds orbits slowly in the background. Cinematographer Emmanuel Lubezki (The Tree of Life; Children of Men) uses his lens as a portal for spiritual meditation on the entire idea of being lost, far from home, terrified yet determined to make it back.

A radiant, resourceful and believable Sandra Bullock is medical engineer Ryan Stone, out on an extended spacewalk for repairs along with veteran astronaut Matt Kowalski (George Clooney). Sudden malfunctions place most of the film in Bullock’s hands, and all of the anxiety in her character’s cascade of mood swings.

A gripping (no, really. This film will have you unable to breathe during the final 20 minutes.) story of panic in space Gravity is nonetheless an allegorical loveletter to our world, as if the further away we soar from home, the more closely we can understand and long for its ineffable sanctuary.

A daring filmmaker, Cuarón has done something smart, unexpected, and ultimately profound. He bets his film on a single character – a female medical engineer on a mission to the Space Shuttle. She inhabits the turf staked out in legions of space and scifi epics for male occupation.

Bullock doesn’t so much feminize the perilous extraterrestrial expanses, as humanize them. By mining her memories of loved ones on earth, she insists on the ties that bind us to home.

Facing perils no Pauline ever dreamt, her character goes through every stage of the cross, or to use another metaphor, every stage of withdrawal—terror, panic, acceptance, and finally sheer grit. She is magnificently each and everyone of us as she confronts the unknown terrors of endless, pitiless space. Space without end. And that can only lead to one of the most memorable reunions ever created on film.

You can tell I found Gravity, well, inescapable. The best film of the year.