There's a new resident in Castle Key - and somebody is watching him! Scott, Jack, Emily and Drift soon suspect that the new resident is an enemy spy. It explains the bullet-proof glass in the windows of his house. And the MI5 agent who is clearly keeping tabs on him! But what is an enemy spy doing in Castle Key?
Series: Adventure Island (Book 10)
Paperback: 192 pages
Publisher: Hachette Children's Group; UK ed. edition