After a break from their trips in the tree house, Jack and Annie are delighted to find that it's back! Morgan le Fay needs their help, but they'll have to become Master Librarians first, and that means solving four riddles. For the first one, Morgan sends them deep into the middle of the ocean. Jack and Annie ride in a mini-sub and meet jellyfish, sea horses and an octopus. But there are some scary sharks in the deep and the friendly dolphins have to come to the rescue. . .
- ISBN10 1446495493
- ISBN13 9781446495490
- Publish Date 30 March 2012 (first published 1 January 2009)
- Publish Status Active
- Publish Country GB
- Publisher Penguin Random House Children's UK
- Imprint RHCB Digital
- Format eBook (EPUB)
- Pages 80
- Language English