The Witch's Dog and the Treasure Map by Frank Rodgers
Puffin Books ISBN 9780141321851
Wilf, the witch's dog, is playing a pirate in the school musical. But when Sly Cat and Tricky Toad find a treasure map and cast a spell on it, Wilf and his friends find themselves face-to-face with some real pirates! Will they all have to walk the plank, or can Wilf come up with a magic idea to save them?