Documentary presenting an intimate portrait of one of Britain's most charming wild animals, following a family of water voles living on a canal in Derbyshire though a typical year. The picturesque Cromford canal used to serve the regions cotton mills. Now, having been deserted, it serves as a perfect water vole paradise. For these hyperactive little mammals, a year is nearly a lifetime. They spend their lives in a frenzy of activity, swimming, feeding and breeding - the latter most neccessary, since water voles are becoming a rarity these days.