Capt. Mike Sack was leading a whale-watching tour back to shore near Moss Landing, Calif. when he saw a group of humpbacks feeding.
The captain slowed his boat to give his passengers a better view, joining a group of kayakers who had stopped for a closer look.
What happened next shocked everyone — and was captured in an incredible video posted to YouTube on Sunday. (Watch below.)
A massive humpback leapt out of the water and landed right on a kayak carrying two people.
"They came very close to getting crushed to death by the mighty humpback whale," Sack wrote in a Captain's Log, where he also posted some photos of the encounter.
Both kayakers were thrown into the water before other paddlers rescued them, the Monterey Herald reported.
They were miraculously unhurt — but one of them said the whale's body came so close to him that he could feel the animal falling.
"[Kayaking is] a dangerous sport, just like surfing," Sack told the Herald. "If you want the thrill of a lifetime, go kayak whale-watching. But beware that it's not a Disneyland ride out there."
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