For more than a century the giant squid was reconstructed from damaged strandings, fragments in sperm whale stomachs and the circular scars those suckers leave on whale skin. No one had recorded a living animal in the deep sea.
In September 2004 Tsunemi Kubodera and Kyoichi Mori suspended a baited line with an automatic camera off the Ogasawara Islands. A giant squid attacked the bait at around 900 metres and was photographed over roughly four hours before tearing free, leaving a tentacle behind. The same team filmed a live animal at the surface in 2006, and video of one in its deep habitat followed in 2012, and again in the Gulf of Mexico in 2019.
The footage corrected the picture. The squid attacked the line actively rather than drifting passively as some had assumed. Length claims remain the murkiest part of the subject: tentacles stretch badly in dead specimens, and the frequently repeated figures of eighteen metres or more are not supported by careful measurement, with reliable totals closer to thirteen metres for females.