The Enid Blyton Adventure Series

Book 6: The Ship of Adventure (Part 1) (1x16)

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Bill and Allison are going on a cruise around the Channel Islands for their honeymoon. But Sir George orders Bill to drop everything in order to get on the trail of Slade - a villain. Allison is devastated. The children suggest that they go on the cruise with her instead. But when Lucy-Ann buys an Galley ship in a bottle that Slade is looking for, the children find themselves in terrible danger.