Ron Takeda and Tavis Boise were a few miles off the coast of Santa Barbara when they noticed the large mass trailing behind them.

"Tavis, is it a dolphin?" asked Takeda as he stood on his foil board, a specialized form of surfing, propelling himself through the waves. Boise, who was filming their run, recognized the question as an ominous sign - the veteran surfers are familiar enough with dolphins that Takeda should have recognized one immediately.

It was, they quickly determined, a massive shark in hot pursuit of Takeda. The creature followed him closely, its fin poking above the water, as he moved at about 10mph.

Boise captured footage of the experience that has since gone viral. In the video, the animal can be seen chasing Takeda for about a minute. Boise can be heard shouting "Don't fall!" as his path diverged from Takeda's, then: "Oh my God, it's coming for you!"

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