The incredible story of 25 of the world's most secretive & deadly fighting units, from the Spartans of Ancient Greece to modern-day SAS & Navy Seals who dare to perform raids in the heart of enemy territory whatever the odds. The covert operations, methods, & dark secrets of the units, are exposed, revealing what makes a supreme military unit. The gripping stories of battles & special operations through historical sources & personal narratives. Details of the special skills behind a top unit's method. Illustrations, photographs, & fact boxes giving the lowdown on each unit.