The Enid Blyton Adventure Series

Book 6: The Ship of Adventure (Part 3) (1x18)

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The children continue the search to find where the map leads, with Slade and Igor in close pursuit. After getting a message from home, Allison discovers that she has been tricked. Bill arrives at the ship and searches for clues as to the children whereabouts. In a packet of developed film he recognises Slade and quickly realises that the children are in enormous danger.