A charter boat group got a rare sight when they went out looking for sea turtles and stingrays during a snorkeling excursion and ended up spotting a nearly 12-foot great white shark.

Capt. Chris Muller took a group of foreign exchange students out to Alligator Reef in the Florida Keys Saturday.

They had just gone in the water when Greg Schlosser, the HappyCat's first mate, saw the shark, according to The Miami Herald.

"I've never seen anything like this in my life, especially not in the Keys, and I've swam with a lot of sharks," Muller told the Herald.

Muller and Schlosser got the students out of the water, then watched as the shark circled the vessel for about 45 minutes, according to WPTV.

Muller used an underwater camera to capture footage of the shark.

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"The funny thing was some fishing boats came back in stating the fishing sucked," Muller said in a comment on YouTube. "Hard to believe one big fish will do that to such a large area but perhaps just a coincidence."

Muller took the group to another area to snorkel.

"The shark didn't follow us," Muller told The Herald. "He stayed on the deeper, southern end of the reef."