In a terrific performance that encompasses countless attitudinal, emotional and physical shifts, Joaquin Phoenix eases into the lead role with equal parts raw pain, ironic humor and eventual mellow acceptance.

The movie radiates considerable compassion, sensitively addressing issues including addiction, recovery and forgiveness. Joaquin Phoenix’s raw, wiry performance never strives for greatness, which only makes it all the more affecting.

Some will find it entirely too sentimental, others a tad repetitive (Callahan tends to repeat the same stories), but it’s hard to argue with a movie that celebrates the kind of recovery he went through.

What makes Phoenix’s performance especially exciting is that you’re watching not just a character go from chaos to self-possession but an actor, too.

The uplifting nature of this true story naturally triggers Van Sant’s pesky sentimentality, with scenes that recall the hug-it-out, therapeutic catharsis of Good Will Hunting. But this is still the writer-director’s most formally interesting, emotionally involving movie in a decade, however little that may really be saying.