: The Famous Five: Five go to Billycock Hill (No:4031)
: Enid Blyton
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: In book sixteen, it's holiday time at Billycock Hill and the Famous Five make new friend - a real pilot! But when he disappears with top secret equipment, the Five begin to wonder if their new friend could be a spy, or worse, a traitor.
Whatever his motives, the gang feel duty-bound to investigate...