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Killer Sharks vs. Killer Whales

Two fierce predators face off in a showdown atop the ocean food chain on Nat Geo.
04:27 | 02/28/2013

Transcript for Killer Sharks vs. Killer Whales

When it comes -- fearsome creatures that lurk beneath the waves sharks have long held the upper hand in everything from horror movie casting today. Reelect he -- nightmares but they're not course the... See More
This transcript has been automatically generated and may not be 100% accurate.
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