Why the underwater world captivates

Joe MacInnis has spent his life going where very few people ever have — beneath the ice at the North Pole, down to the wreck of the Titanic, and into the deep waters of Lake Superior to visit the Edmund Fitzgerald. Now 88, the Canadian physician and deep-sea explorer looks back on a lifetime of high-risk exploration. He talks about the moment he caught “sea fever” as a teenager, what those extreme environments taught him about fear and teamwork, and why leadership — not technology is what really matters when survival is on the line.