The red-and-white squid was filmed by Diving Shop Kaiyu owner Akinobu Kimura.
"My curiosity was way bigger than fear, so I jumped into the water and go close to it," he told CNN.
He then swam with the animal as he helped guide it back to the deep ocean.
"This squid...looked lively, spurting ink and trying to entangle his tentacles around me," Kimura said.
The squid was 12 feet long, which is about the length of a Mini Cooper.
As big as that is, it is just a baby giant squid — the creatures are known to grow to as long as 43 feet, or about the length of a bus.
For hundreds of years, the squid was so rarely seen that it was considered a myth.
Watch footage from the Christmas Eve spotting here:
Michelle Broder Van Dyke is a reporter and night editor for BuzzFeed News and is based in Hawaii.
Contact Michelle Broder Van Dyke at email@example.com.
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