Watch an encore of "Blackfish" on CNN, Saturday, October 26 at 7 p.m. ET and Sunday, October 27 at 9 p.m. ET.
Colin Baird still remembers the day he got the call from work more than 23 years ago, when he learned of his co-worker's fate.
"We need you to come in," said his colleague from the Sealand of the Pacific in Victoria.
His fellow trainer, 20-year old Keltie Byrne, had slipped and fallen into the orca tank. Byrne was an exceptionally strong swimmer but she was no match for the aquarium's killer whales.
"She tried to get back out and the other girl tried to pull her up, but the whale grabbed her back foot and pulled her under," eyewitness Nadine Kallen told CNN affiliate CTV in 1991. "And then the whales -- they bounced her around the pool a whole bunch of times, and she was screaming for help.
"They tried to grab her with sticks, but they couldn't get her," Kallen said. "And she finally didn't come up any more."
There were three orcas at Sealand at the time -- two females, Haida and Nootka, and Tilikum, the sole male. Tilikum would later become infamous for the 2010 killing of SeaWorld trainer Dawn Brancheau.
Tilikum -- or "Tili," as he was known -- was popular and "very easy to work with," Baird recalled.
"He was very easygoing, he learned quickly, he learned well, very responsive," he said. "You know, he was probably my favorite of the three."
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