John Callahan was a hopeless, Portland-based alcoholic, starting his days desperately trying to get the first drink that would keep his buzz going from the night before. Yet he managed to maintain a sly charm, both as a means of always scoring that next drink and to woo the next woman into bed with him.

But when he became a quadriplegic after being the passenger in a tragic drunk-driving accident, Callahan’s life gradually and improbably changed for the better. He managed to achieve sobriety, and with little ability to do anything else, he started sketching out his darkly comic thoughts into single-panel, “New Yorker”-magazine style cartoons that reflected his view of the world and made him a controversial yet nationally-regarded media figure.

His loopy life story forms the basis for the new film “Don’t Worry, He Won’t Get Far On Foot,” starring Joaquin Phoenix as Callahan and an almost unrecognizable Jonah Hill as his Alcoholics Anonymous group leader Donnie in what will surely stand as two of the best performances of the year. Directed by Gus Van Sant (“Good Will Hunting”), who often applies quirky aesthetic touches to his films, “Foot” mixes powerful scenes of sadness with profoundly uplifting moments that will surely test the tear ducts of its viewers with doses of humorous charm.

The film opens on Callahan scrambling to a liquor store, hoping to avoid the shakes and pains that come with alcohol withdrawal, and Van Sant effectively building tension from the very beginning as he darts through traffic to get his fix fast. Those unfamiliar with the accident that changed his life will cringe with every swerving car, and the tension is ratcheted up when he goes out to party that night with a devilishly charming new acquaintance named Dexter (Jack Black at his trademark best).

After pounding drinks for hours at parties, bars and strip clubs, the two pass out in Dexter’s car while driving home. Dexter walks away largely unscathed but disappears, while John finds himself in a long-term rehab center due to his new paralyzed state. Thinking his life is over, he finds hope in a counselor named Annu (Rooney Mara), who encourages him to find new purpose in his sobriety and wicked humor, which is manifested in cartoons that have a uniquely crude style due to his difficulty with drawing.

A couple of examples are a cartoon in which an Old West posse finds an abandoned wheelchair in the desert and its leader says the film’s title line, and a picture of Jesus crucified on the cross while thinking “TGIF.”

He found both success and controversy with his cartoons in the alternative newspaper Willamette Week, Callahan’s work also appeared in the Pasadena Weekly from 1989 to the late 1990s. He created two animated series that dealt with quadriplegia, the children’s show “Pelswick” and the darker HBO series “John Callahan’s Quads!” before his death in 2010 at age 59.

Callahan has to overcome his immense, lifelong bitterness and insecurity over the fact that his mother abandoned him as an infant. This journey to forgive the people who have hurt him and seek forgiveness for those whom he has hurt while making his first grasps at faith in a Higher Power is both universally relatable and unforgettable.

Aside from his broodingly intense Oscar-winning performance as Johnny Cash in 2005’s “Walk the Line,” Phoenix has built his career upon playing all manner of dark outsiders, but he’s never been more charming than here. He oozes sleazy charisma in his early drunk scenes, but when he starts to grow into being a better human being, it’s almost stunning to see Phoenix exude happiness and a sense of grace.

He’s matched for excellence by Hill, who has developed into a daring, chameleonic young actor who racked up two Oscar nominations (for “Moneyball” and “The Wolf of Wall Street”) by the time he was 30. Hill veers wildly with nearly every film between being morbidly bloated and surprisingly thin, and combining a slender frame with a blonde-Jesus look as Donnie, he is utterly transformed. He and Callahan may have odd ways of finding a Higher Power (both jaded against a traditional sense of God, they focus on the murderous doll Chucky from the “Child’s Play” series of horror films), but the results of their quest are deeply touching. Add in Jack Black’s turn as Dexter, particularly a late-movie scene in which John offers him forgiveness, and you’ve got an acting trifecta that is a definite winner.

Director Van Sant applies several intriguing ways for Callahan to relate his story: blending together scenes of him recounting memories in Alcoholics Anonymous meetings, a speech before a group, creepily vague childhood memories and animations of his most outrageous cartoons as he shows a group of young teenage boys a sketchbook of his work. The effect draws viewers in on several levels and allows a deeper focus than a straightforward telling of his story would.

As a result, “Foot” gets very far in making a mark as one of the year’s best films and a movie that will stand the test of time. n

“Don’t Worry, He Won’t Get Far On Foot”: A