The men were fossil hunters from Newcastle, Wyoming, less than an hour's drive from Hill City. The box was full of scraps and fragments of triceratops material, Theisen recalls, with hardly a decent bone in the bunch. After asking the questions any reputable fossil dealer would ask -- Were the bones found on private land? Did they have the landowner's permission to take them? -- Theisen offered to buy the lot for a couple hundred bucks.
The men quickly accepted. They told Theisen they could bring him better bones if they knew what to look for. "They said there were a few more bones lying around this ranch, and they weren't sure what they were worth," Theisen recalls. "Would I go out and look at them and give them some pointers?"
Theisen was not the man to say no. He had a passion for bones. He found his first fossilized insect behind his parents' garage in Michigan when he was five years old, and he'd been hooked ever since. He'd moved to Hill City years before to work with the Black Hills Institute of Geological Research, a leading private center for fossil excavation and preparation. Although he still assisted BHI on digs and mounting large specimens, he'd since developed his own business as a dealer and restorer. But nothing replaced the thrill of actually going out in the field and getting his hands dirty, unearthing the secrets of a world lost long before Homo sapiens began his short stroll on the planet.
The three men arranged a rendezvous south of Newcastle, not far from the ranch where the bones had been found. Theisen was surprised to see one of the fossil hunters, who called himself Randy, drive up in a county sheriff's vehicle. (According to a dispatcher for the Weston County Sheriff's Department, Randy no longer works there.) Soon they were walking up and down ancient draws and washes, looking for bones.
Randy called over to Theisen, urging him to come look at an area that was littered with bone fragments. Theisen drew closer and spotted three objects that sent his heart racing.
The first looked like a cervical vertebra. The second appeared to be an occipital bone from the base of a skull. The third, the clincher, was a piece of jawbone no larger than the palm of his hand. The bone was distinctively grooved where the teeth had been. Big, meat-shredding teeth, from six to twelve inches in length.
Theisen knew of only one creature with foot-long chompers that roamed the Lance Formation of eastern Wyoming -- a beast so fierce that early fossil hunters called it the "tyrant lizard king."
"Do you know what this is?" Theisen asked.
Randy shook his head.
"This is a T. rex," Theisen said.
Randy's partner was summoned to hear the tremendous news. Finding a Tyrannosaurus rex is every fossil hunter's elusive dream. At the time, only 22 T. rex specimens had been found, and in only two cases had more than 50 percent of the skeleton been recovered. The pieces Theisen had spotted were significant, and who knew how much more of the creature might be buried below?
The shock of the discovery was still sinking in, Theisen says, when his two companions "started acting funny." Theisen knew that big finds on a dig sometimes produced odd behavior -- "People get weird, like they won the lottery or something," he explains -- but this was different. The men exchanged hinky glances, looked around nervously for passing cars. They did not warm to Theisen's suggestion that they go talk to the landowner right away.
It began to dawn on Theisen that maybe Randy and his friend didn't have the landowner's permission to be collecting fossils after all. If that was the case, then Theisen had bought stolen goods from them, and his mere presence at the site made him an unwitting accomplice to yet another crime.
In the T. rex registry compiled by the Black Hills Institute, Leon Theisen is listed as the discoverer of Specimen #23. But Theisen is quick to point out that he merely identified what Randy had already stumbled upon. "It wasn't me that discovered it," he says. "It was one of the other trespassers."
It was a fitting beginning to the strange dealings that would soon engulf Theisen's find -- controversies and legal squabbles that continue to this day, with no hint of resolution. Discovered by people who had no legal claim to it, the T. rex has been on a rampage ever since. The fossil has become a magnet for lawsuits and intrigue, for hush-hush transactions and mind-boggling expense. It has been hailed as a significant find by some experts, denounced as an overvalued assembly of fragments by others. Its ownership is being contested in Denver's federal court, and its very existence has been challenged in a divorce case in California. For now, at least, its odyssey may reveal more about the pitfalls of the modern fossil business than it does about life as the king of predators eons ago.