Documentary that uncovers all the facts behind the biology and behavior of the extinct sabre-toothed cat, often misnamed a tiger. Computer-animation techniques bring the formidable predators back to life. The sabre-toothed cat was heavier than a lion, more ferocious than a tiger, and armed with a pair of six-inch canines. Fossil studies and biomechanical models reveal its strength and size. The program also examines how the sabre-tooth re-evolved five separate times, adjusting in tandem with its environment, and how the disappearance of larger prey like the mammoth may have spelled its doom.