This squid is big – colossal, even. It can grow to over 40 ft. in total length, longer than a school bus, and its mantle is as wide as a semi truck tire. Despite having a boneless hydrostatic (fluid-supported) skeleton, it tips the scales at 1,000 lbs. – that's the weight of 1,334 full 12-ounce soda cans, a giant Pennsylvanian butter sculpture, and the heart of a Blue Whale (Balaenoptera musculus). Its eyes, larger than soccer balls, are the largest in the animal kingdom. The Colossal Squid is an example of a phenomena known as abyssal gigantism, where deep-sea species are larger than shallow-water counterparts (this is most likely a result of greater pre-maturation growth and the tendency of lifeforms in colder water to have greater mass).
Colossal Squid are relatively sedentary predators – they lie in wait for their prey, expending little energy. A hunting Colossal Squid usually swims upside down with their lifted above their head in what is called the "cockatoo" position (here's some footage of a much smaller squid exhibiting the same behavior). This gives the squid's giant bioluminescent-"searchlight" eyes a greater field of vision.
Let's focus for a moment on the Colossal Squid's world class eyes. These peepers are a foot in diameter, the single refractor lens the size of a small orange. The lens focuses light onto a retina, just as vertebrate eyes do. Unlike vertebrates, however, cephalopod eyes lack a cornea and adjust themselves not through a change in the curvature of the lens but through the movement of the eye. Unlike most squid, the Colossal Squid's eyes are forward-facing and provide stereoscopic/binocular vision. The eyeballs are also line with photophores that produce light through bioluminescence. Although these eyes are limited in some ways humans would find quite problematic (for example, they cannot distinguish color), they maximize the limited light available in the ocean's depths, their size combined with the squid's well-developed optic lobe allows for very high spatial resolution, and they allow the squid to spot from a distance of 120 m. their greatest predator – the Sperm Whale (Physeter macrocephalus).
Juvenile squid, which hatch from a gelatinous, floating mass of eggs, are easy prey for a variety of deep-sea fish and squid. They grow to maturity in 1-3 years. Instead of using a hectocotylus (sexually-developed arm) to insert a spermatophore into the the female, males's genitals directly implant sperm into their mates.