21 Grams

“How much does life weigh?”

In Phoenix, a dying mathematics professor (Sean Penn) receives a heart transplant and learns it came from a man killed in a hit-and-run accident. A grieving mother (Naomi Watts) whose family died in that crash and the born-again ex-convict (Benicio del Toro) behind the wheel become bound by that single moment. Iñárritu splinters their stories across time until they finally stand face to face in a bathroom, trembling.