21 Grams

Last night I watched Alejandro Iñárritu's 21 Grams, a film about life and death and revenge and forgiveness and redemption.
Sean Penn plays Paul Rivers, who is dying and needs a heart transplant. Benicio Del Toro plays Jack Jordan, an ex-convict who has turned to fundamentalist Christianity in order to redirect his life. Naomi Watts plays Cristina Peck, a reformed cocaine-addict.
Their stories merge when Jack runs over Cristina's husband, Michael, and Cristina allows the hospital to give Paul her husband's heart.
Jack turns himself in, and his faith is severely tested in gaol. Cristina ends up back on cocaine. Paul finds out about what it cost Cristina and Jack for him to live. He struggles with whether he should try to reconcile them or avenge Michael's death.

The title of the film comes from the experiments of Dr Duncan MacDougal, who claimed that the human body lost 21 grams at death. He rekoned this was the weight of their departing soul.* In this film, Iñárritu raises questions about the 'weight' of life, and what it is that leaves our bodies when we die. He also wrestles with questions about why people have faith and why God would allow such awful stuff to happen to people.

*Ian Sample from The Age got a bit upset about this, here. I think he missed the point.