"I was 7 when I first saw the cartoon book, first read it," Cousteau,
now 38, said. "It stuck in my mind as a great idea. We went one step
further; I didn’t want something rigid that didn’t move."

Propelled by a wagging tail and covered in a flexible, skinlike
material, the sub—created by Cousteau and a team of scientists and
engineers—swims silently.

The steel-ribbed, womblike interior is filled with water, requiring Cousteau to wear a wet suit and use scuba gear to breathe (see photo).

George Lauder is a professor of organismic and evolutionary biology at
Harvard University in Cambridge, Massachusetts. He has not personally
seen the shark sub, but said that if the contraption moves as
advertised, the team deserves congratulations.

"It is notoriously hard to produce natural-like swimming motions of fishes with robotic models," Lauder commented in an e-mail.

More here.