Last spring, the otters’ home flooded. Now the water is high again.

Young otter Sedge believes he can save his holt from another flood – but he has to be brave enough travel downstream for help.

Downriver, the beaver lodge is also at risk. Silken – who is too small and weak to do the work needed to strengthen the beavers’ dam – feels something calling her up the river.

As the two animals unknowingly swim towards each other, they are drawn to the spirit of Greenriver, who takes the form of a snow-white otter, Lady River.

But will Lady River hear their plea for safety?