Kumo no Ito (2000)

Kandata spent his life as a ruthless thief and now suffers among the damned in hell. Yet the Buddha remembers one small act of mercy from his earthly life: Kandata once chose not to crush a spider. From paradise, a single silken thread is lowered into the darkness, offering him a narrow path upward.

Kandata climbs desperately toward salvation, but when he notices countless other sinners following beneath him, fear and selfishness overtake relief. The fragile thread becomes a final test of whether one good deed can matter when the heart that performed it has not truly changed.