The narrative follows two friends on a canoeing trip down the Danube who choose to camp on a remote, deserted island choked with thousands of restless willow bushes. From the moment they land, they experience a growing sense of unease, as if their presence in this wild, untrodden landscape is deeply resented by unseen elemental forces. The river itself feels unnaturally alive, and the endless thickets of willows seem to move with a collective, hostile purpose.
As night falls, the atmosphere thickens into an oppressive dread. Strange, disquieting sounds fill the air—a continuous, gong-like humming that seems to emanate from another dimension. Both men find their nerves strained to the breaking point, though they react differently; one grows increasingly fearful of a malevolent intelligence closing in around them, while the other struggles desperately to maintain a rational, skeptical outlook.
Physical manifestations of this invisible hostility begin to multiply. Provisions vanish mysteriously, the canoe's steering paddle is damaged, and a tear appears in the hull as if deliberately inflicted. In the dead of night, towering bronze-colored figures are glimpsed rising from the willows, and a heavy, suffocating pressure descends upon their tent, threatening their sanity and their lives.
Tension peaks as the travelers realize they are trespassing upon the frontier of an alien world whose inhabitants view them as intruders destined for sacrifice. The psychological burden becomes almost unbearable, driving them close to panic and despair as they fight to control their thoughts against the pervasive influence.
By morning, the terror temporarily recedes with the sunlight, revealing a landscape scarred by mysterious funnel-shaped hollows in the sand. Although they attempt to normalize the experience and plan their escape, the oppressive atmosphere returns with the approaching dusk, intensifying their dread of the unseen powers.
The novella reaches its climax when the companions discover a drowned peasant's body caught in the river reeds. The corpse bears the strange, indented marks of the elemental forces, suggesting that another victim was claimed to secure the travelers' temporary reprieve. As the body drifts away, the chilling realization lingers that human presence is utterly insignificant against the ancient and terrifying powers of the wilderness.
