Anna and Matthew Morgan from Stevenage are spending their Easter holidays with their uncle and cousins. Their Uncle Richard, who is a Countryside Warden in the picturesque Usk Valley of south-east Wales, suspects that someone is tipping industrial waste sludge into local waterways. When Anna is woken late at night by the sound of a heavy truck labouring up the hill past Canal House, she becomes suspicious. But how can they find the proof which they need to convince the local police? Or could they possibly catch the criminals themselves??
This book was originally written for German teenagers learning English, but is suitable for all younger readers who love adventure stories.
