Diver Rainer Schimpf was documenting South Africa's annual sardine run when he was partially swallowed by a Bryde's whale

Most of us have a cartoonish idea of what the inside of whale’s stomach looks like thanks to Pinocchio, but diver Rainer Schimpf almost found out what a whale belly looks like for real.

In an episode of Barcroft TV’s web series “Snapped in the Wild” Rainer, 51, recounts the time he was nearly swallowed whole by a Bryde’s whale off the coast of South Africa.

Rainer was 25 nautical miles out from Port Elizabeth, documenting the annual sardine run that occurs off the coast of South Africa, when the terrifying incident occurred. The diver said the sardine run offers animal lovers an unique opportunity to document many of the ocean’s most magnificent creatures, because the spawning event happens so close to shore and attracts all kinds of marine life.

Rainer was in the water trying to film a shark cruising through the giant school of sardines, when “the next moment it got dark, and I felt some pressure on my hip.”

An experienced diver, Rainer said he knew instantly that a whale had grabbed him.

“Nothing can actually prepare you for the event where you end up inside the whale, and then it’s pure instinct,” he added.

Rainer’s instincts told him not to react to the scary situation in fear. Instead of freaking out, the diver took a deep breath and prepared to be taken back under the water by the 20-ton whale.

Shortly after submerging, the whale released Rainer, who swam back up to the water’s surface.

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Rainer returned to his boat unscathed and feeling closer to whales than ever before.

“It happened very fast. And from being on the surface and observing something, I became the inside man and was suddenly inside a whale looking out,” Rainer told Barcroft TV. “It gives me a connection to the whale that I don’t think anyone else had before.”

The diver and witnesses to the incident believe the whale was just as surprised to find a man in it’s mouth.