] we were all riveted by this story earlierhis year, but all we knew at the time was that a deranged kidnapper had grabbed a 5-year-old boy off a school bus. Well, tonight, for the first time in an... See More
] we were all riveted by this story earlierhis year, but all we knew at the time was that a deranged kidnapper had grabbed a 5-year-old boy off a school bus. Well, tonight, for the first time in an exclusive report, abc's pierre thomas lets us listen into the crime and to the extraordinary brave people who brought little ethan home. Reporter: You are about to hear a voice that is every parent's nightmare. I want two kids, 6 to 8 years old. I mean it. Right now! Right now! Reporter: A kidnapper named jimmy lee dykes is on a school bus and he's got a gun. I need two boys! 6 to 8 years old. Two boys. Come on! Reporter: The recordings, obtained exclusively by abc news, tell a story of madness and heroism. This is the voice of the hero who put his life on the line to protect the school children. I can't do it. Do it! Sorry. You're going to have to shoot me. Reporter: Bus driver charles poland stands firm. It's my responsibility to keep these kids -- I can't help that. I can't turn them over to somebody else. Reporter: Dykes turns his attention to a little boy named ethan, sitting directly behind the driver. He's only 5 years old and has autism. Poland pleads, "not ethan." Dykes shoots him five times in front of the terrified children. He could have taken several kids, if it were not for the specific actions of chuck poland. It's amazing that -- the faith that he had. Reporter: Another hero, 15-year-old tre watts, has the courage to dial 911. Oh, my gosh. What's going on? The bus driver's dead. What's he doing now, honey? He took a kid! He took a kid! He took a kid! Reporter: Unbelievable. He stayed calm. He described the subject in detail. Reporter: Dykes takes ethan to a fortified untsdz ground bunker, rigged with homemade bombs. When we identified the ied, it was a game-changer. Reporter: An army of more than 300 police and fbi agents converge on the scene. And with that, a six-day siege begins. But negotiations with dykes grow tense. He is angry with the government. You know I have the knowledge, I have the experience. I have the ability and I have the to show just how corrupt this system is. He began losing patience with us and issuing ultimatums. He was handling his weapons. Reporter: The decision is made to take the bunker by force. They immediately received gunfire from mr. Dykes. Reporter: There was an ied inside the bunker, as well? Yes, sir. He was in the process of trying to detonate it. Reporter: Dykes is shot and killed in the confrontation. Ethan and the agents, remarkably, escape injury. The children on that bus, hundreds of police and fbi agents, all displayed courage under fire. But they all point to the sacrifice of the hero bus driver, charles poland. He laid down his life for ethan and the children in his care. Diane, we spoke to mr. Poland's wife. She's so proud of her husband. And she said he was so much more to her than a hero. And to all of those children who owe him everything. Thank you. Thank you, pierre. And we nope there's a lot more in your reporting and it will be on tonight on "20/20," it will be called "cat and mouse." Be sure to watch it at 109:00, 9:00 central.
This transcript has been automatically generated and may not be 100% accurate.