In new television specials, Jacques Cousteau's grandchildren carry on his planet-saving mission.

Oceanographer Jacques Cousteau introduced millions to the wonders of the deep sea via his documentaries, books and conservationist efforts, a legacy his son and grandchildren have embraced with equal passion. For siblings Fabien and Celine Cousteau, who join their father in the latest installment of Jean-Michel Cousteau’s Ocean Adventures entitled Call of the Killer Whale, a documentary about orcas debuting on PBS Apr. 22 at 8 p.m., going into the family business was inevitable.