Grey Wolves (Henderson's Boys #4) - Robert Muchamore

APRIL 1941
With no European allies, Britain has to ship fuel, weapons and more than half of its food across the Atlantic from Canada and the United States. But slow moving cargo vessels make easy prey for packs of German submarines.
Henderson and a team of young agents must go undercover to sabotage German U-Boat operations. If they dont succeed, the British people face starvation.

Please note this copy has light scuffs on the edges of the covers

ISBN: 9780340999165
Size: Paperback, 448 pages
Publisher: Hodder & Stoughton
Year: 2011