Throughout history, there have been many terrifying stories and legends about sea monsters based on the real-life giant squid.(1,2) Though these stories may be exaggerated, the giant squid is truly a mysterious, intelligent, and gigantic creature of the deep.(1,2) It can reach a total length of about 18 m (59 ft) and a weight of about 900 kg (1980 lbs) (though, since the tentacles stretch after the squid dies, some high size claims may not be accurate(2));(1,3) on average it is around 11-14 m (36-46 ft) long and weighs around 455 kg (1000 lbs) or less.(1,3) This huge squid lives in deep, cold ocean waters around the world,(1,3,4) especially where the ocean floor slopes down off the coasts of continents and islands,(1,3,5 )often choosing to live near places where there are particularly large amounts of food, such as underwater canyons.(6) Because they live so deep in the ocean, we know little about the behavior of giant squid.(2) We do, however, know that they grow very large extremely quickly and so must have a huge appetite(7)—and they certainly are equipped to catch food! Unlike in other squids, the giant squid’s two long tentacles are covered with small suckers and bumps which allow the squid to “zip” the two tentacles together into a single long weapon.(2,4) On the tips of the tentacles are a set of closely-packed special suckers with sharp tooth-like structures on them which the giant squid uses to attack and grab its prey.(2,4) The giant squid also makes use of its enormous eyes—at up to 25 cm (10 in) across,(7) the biggest eyes of any animal(1,7) except for the giant squid’s relative, the colossal squid (Mesonychoteuthis hamiltoni)(8)—to hunt in the near-darkness of the deep sea.(3,4) From examinations of stomachs as well as other methods,(9,10) scientists have learned that the giant squid eats many kinds of animals, including fish, crustaceans, and squid (possibly even other giant squid!9).(1,3,9) As fierce a predator as it is, though, it often gets eaten by sperm whales(1,2,3,6) and sleeper sharks.(1,11) With so many relationships with other species, this incredible squid may play a major role not just in sailors’ stories, but also in the complicated deep-sea food chain.(3,10).