It was summer, and Primrose woke knowing that it was going to be a very special day. The sun was already warm, and a light breeze stirred the leaves and branches of Brambly Hedge. It was a perfect day for a sailing adventure.

Leaving the hedge behind, Dusty, Poppy, Primrose and Wilfred set off downstream in Dusty's boat the Periwinkle, on a journey that will take them all the way down to the sea. But it isn't all plain sailing.

The mice have an important mission to fulfil before they can return to Brambly Hedge...