SPRING
The wooden doors of a gated threshold open on a small monastery raft that floats upon the tranquil surface of a mountain pond. The hermitage's sole occupants are an Old Monk (OH Young-soo) and his boy protege Child Monk (KIM Jong-ho). While exploring the world in and around their secluded idyll, Child Monk indulges in the capricious cruelties of boyhood. After tying stones to a fish, a frog, and a snake, Child Monk awakens to find himself fettered by a large stone Old Monk has bound to him. The old man calmly instructs the boy to release the animals, promising him that if any of the creatures die "you'll carry the stone in your heart for the rest of your life."

SUMMER
The doors open again on Boy Monk now aged 17 (SEO Jae-kyung) who meets a woman (KIM Jung-young) making a pilgrimage with her spiritually ill daughter (HAYeo-jin). "When she finds peace in her soul," Old Monk reassures the mother, "her body will return to health." The girl awakens desire in Boy Monk and the sensual flirtation between the two of them culminates in passionate lovemaking on pond-side rocks. After a furtive but tender tryst in the abbey's rowboat, the lovers are discovered by Old Monk. The girl, now healed, is sent back to her mother. Forsaking his monastery home, the infatuated Boy Monk follows her.

FALL
Long absent from the monastery, Young Adult Monk (KIM Young-Min), now a thirty year old fugitive, returns to the abbey raft still consumed by a jealous rage that has compelled him to commit a violent crime. When Young Adult Monk attempts penitence as cruel as his misdeed, Old Monk punishes him. The Old Monk instructs Young Adult Monk to carve Pranjaparpamita (Buddhist) sutras into the hermitage's deck in order to find peace in his heart. Two policemen arrive at the abbey to arrest Young Adult Monk but thanks to Old Monk, they let Young Adult Monk continue carving the sutras. Young Adult Monk collapses from exhaustion and the two policemen finish decorating the sutras before taking Young Adult Monk into custody. Alone again, Old Monk prepares a ritual funereal pyre for himself.

WINTER
The doors open on the now frozen pond and abandoned monastery. The now mature Adult Monk (played by director KIM Ki-duk) returns to train himself for the penultimate season in his spiritual journey-cycle. A veiled woman arrives bearing an infant that she leaves in Adult Monk's care. In a pilgrimage of contrition, Adult Monk drags a millstone to the summit of a mountain overlooking the pond. As he gazes down on the pond that buoys the monastery and the mountainsides that gently hold the pond like cupped hands, Adult Monk acknowledges the unending cycle of seasons and the accompanying ebb and flow of life's joys and sorrows.

... AND SPRING
The doors open once again on a beautiful spring day. Grown from a child to a man and from a novice to a master, Adult Monk has been reborn as teacher for his new protege. Together, Adult Monk and his young pupil are to start the cycle anew...