Transcript for Man bungee jumps off highest tower in Macau

Finally tonight here, America strong. The husband, father and grandfather who has conquered so many challenges, and turning 86 years old, he sent us this. He's from Washington, D.C., a father, husband, grandfather. And retired scientist from the national cancer institute. He's also a black belt in tae Kwon do. He's gone skydiving, climbed kilimanjaro. He went running with the bulls. But just a few years ago, he faced his toughest challenge yet -- complications during a surgery left it nearly impossible for him to walk. But he conquered that, too, and so when it came time to celebrate his 80th birthday this week, he had an idea and invited us along. Thank you, David, for sharing my 80th birthday with your viewers. Reporter: Taking us 764 feet up to the world's highest bungee jump in China. He was ready. I'm ready to go. Let's get on. Reporter: Strapping him in, walking out to that ledge and down below, anxiously watching, his wife, Mary, and daughter, sandy. And then, the countdown. Five, four, three, two, one -- Reporter: The jump over, but still hanging, he had this message. What an 80th birthday, I got to tell you. Reporter: And then, back on land. Happy birthday! Reporter: And his wife and daughter, glad he's back on solid ground. Happy 80th. Better you than me. Thanks for watching here on a Thursday night, I'm David Muir. I hope to see you right back here tomorrow. Announcer: This is WCVB

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