Tan is just another farmer, following the path, when the seal on his soul-powered plow bursts, causing a mass exodus of ghosts from the reincarnation engine. Instead of being carried off by the wind, these ghosts flee to Tan's tangerine groves, reveling in their freedom.
Tan confronts them only to learn that one of the souls is his deceased uncle, Lau Weng, and he's forced to offer hospitality.
Souls laboring in the reincarnation engines grow more solid as they work off their past live's debts and prepare to be born again. But without the work to sustain them, Lau Weng and his ghostly compatriots rely on Tan and his wife Heng to support them.
Lau Weng was never a favored Uncle, and even less favored as a ghost. Caught between death and re-birth, he'll do anything to remain alive. Tan is honor-bound to abide by the laws of hospitality, yet honor-bound to feed his family, too, and he can do nothing to stop Lau Weng.
But everything changes, once Lau Weng decides he's had enough of his ghostly half-life and takes over Heng's body.