US pre-teens discover rare juvenile Tyrannosaurus rex; Science expedition chronicled in extraordinary documentary

Marmarth, ND – Three keen-eyed young fossil hunters made the discovery of a lifetime when they found the remains of a rare teenage Tyrannosaurus rex that could rewrite history, scientists and filmmakers announce today. 

The boys — brothers Liam and Jessin Fisher, 7 and 10 years old at the time, and their 9-year-old cousin, Kaiden Madsen — spotted a large fossilized leg bone on a walk in the Hell Creek badlands area of North Dakota on July 31, 2022.

Believing they had found a relatively common duckbill dinosaur, they sent a photo to family friend and Marmarth native Dr. Tyler Lyson, Associate Curator of Vertebrate Palaeontology at the Denver Museum of Nature & Science, who organized an excavation that began 11 months later, adding the boys and a sister, Emalynn Fisher, now 14, to his team of palaeontology volunteers and experts. 

Brushing off a tooth soon after arriving, Dr. Lyson realized the boys had found a notorious T. rex — a very rare juvenile specimen. The team unearthed it in 11 days after an estimated 67 million years in that spot.

Airlifted onto a truck by a Black Hawk helicopter, giant plaster jackets containing the “Teen Rex” are now at the Denver Museum of Nature & Science, where the public will be able to follow the fossil’s preparation in the new “Discovering Teen Rex Prep Lab.” 

Remarkably, the secret of the teenage T. rex find held for nearly two years while an award-winning documentary crew, renowned palaeontologists, several of the world’s foremost natural history museums, and top animators partnered to present the kids’ discovery in dramatic cinematic fashion.

A crew from Giant Screen Films (GSF), a world-leading producer of large-format documentaries, was embedded with expedition and had 8K cameras rolling as the fossil’s diagnostic features were unearthed, including the eureka moment when Dr. Lyson confirmed that the kids had found a Tyrant King. 

As a result, audiences can experience the adventure of the discovery and excavation through an immersive new giant screen documentary, T. REX, narrated by New Zealand actor Sir Sam Neill, who portrayed Dr. Alan Grant in the Jurassic Park films. 

With hat tips to famous specimens, landmark discoveries, and wild cinematic depictions over the last century, GSF’s documentary intercuts the remarkable expedition with cutting edge computer graphics that bring the iconic T. rex—from hatchling to hulking adult—to life on the world’s largest screens. 

Extremely rare juvenile T. rex

‘Juvenile rex specimens are extremely rare,” said Dr. Lyson, who found his first dinosaur in the same area at age 6. He credits his own career to the mentorship of paleontologists who invited him to join their work in the Badlands. 

“This find is significant to researchers because the ‘Teen Rex’ specimen may help answer questions about how the king of dinosaurs grew up,” he said.

The size of the specimen’s tibia (shin bone), 82 cm, compared to the size for a full grown adult’s tibia (112 cm) suggests that it was 13 to 15 years old when it died around 67 million years ago.

Paleontologists also estimate that “Teen Rex” likely weighed around 3,500 pounds (1,632 kg), measured roughly 25 feet (7.6 m) from nose to tail, and stood about 10 feet (3 m) in height—about two-thirds the size of a full grown adult.

“It’s remarkable to consider how T. rex might have grown from a kitten-sized hatchling into the 40-foot, 8,000 pound adult predator we are familiar with,” said Dr. Thomas Holtz, a vertebrate paleontologist from the University of Maryland and renowned T. rex authority. 

He continued, “scientists can really only speculate on how ‘Teen rex’ might have lived and behaved, so discoveries like this one have the potential to provide important new information about those earlier life stages, when fastest growth likely occurred.” 

The experience was especially exciting for Jessin, a dinosaur aficionado and aspiring paleontologist who dressed up as his hero, Dr. Tyler Lyson, for Halloween a few years ago. 

And “helping these kids experience the thrill of their discovery and to be inspired by science is incredibly rewarding to me personally,” said Dr. Lyson, who was himself mentored by leading paleontologists visiting the area when he was very young. 

The boys are keen to visit the “Teen Rex Prep Lab” when it opens and the film debuts in Denver June 21. They are also excited about a later film screening for Marmarth schoolmates to share the thrill of their discovery. 

With Dr. Holtz as lead advisor, the T. REX filmmakers collaborated with a consortium of paleontologists, eight prominent natural history museums, and award-winning visual effects artists to create scientifically accurate models of rex and the Hell Creek prehistoric ecosystem, a highly studied rock formation in the Upper Midwest that contains fossil remains from the Late Cretaceous, the final days of the dinosaurs—from Triceratops to Edmontosaurus. 

Supported by a coalition of leading museums worldwide, the documentary features cameos of SUE, perhaps the most well-known T. rex specimen ever found (Field Museum, Chicago); T. rex WYREX (Houston Museum of Natural History); T. rex THOMAS (Los Angeles Natural History Museum) and HORRIDUS the Triceratops (Melbourne Museum). 

A dream documentary story

“We never could have planned the inspiring story that unfolded in front of the cameras,’ said producer and writer Andy Wood. “Kids finding any large dinosaur is remarkable, but as the shoot progressed, the team realized that we were witnessing something even more rare—a truly historic T. rex discovery. It’s been a real thrill.” 

“This is more than just a documentary—it’s a chance for families to experience the thrill of discovery through the eyes of these young explorers in a format that makes you feel like you’re right there with them,” says co-director/writer David Clark.

“This is the kind of story that documentary filmmakers dream of capturing.”

“Beyond fostering an appreciation of the fun of science, the film sends a message about getting outside and exploring,” said Dr. Lyson. “That’s a really important message that we want to come through—one that I think is just baked into this story.”

T. REX will premiere at select theatres worldwide beginning June 21, opening in 100 cities over the coming months in all immersive museum cinema formats, including large format, IMAX, 3D, and giant dome. 

GSF has also partnered with Rextooth Studios to create a graphic novel to accompany the film.

The fossil was collected on land under the jurisdiction of the Bureau of Land Management (USA), permit ND2023-00084.

T. REX is a Giant Screen Films and D3D Cinema production, in partnership with:

• Field Museum, Chicago
• Denver Museum of Nature & Science
• Houston Museum of Natural Science
• Natural History Museum of Los Angeles County
• in association with
• Cincinnati Museum Center
• Cleveland Museum of Natural History
• Museums Victoria, Australia, and
• New Mexico Museum of Natural History and Science

Giant Screen Films 

Based in Evanston, Illinois, GSF is one of the world’s leading and most active large-format film producers. It has often partnered with the National Science Foundation and pioneered large-format films that push the boundaries of the medium. Through the magic of immersive sight and sound technologies, GSF’s productions challenge the imaginations of children and adults, offering inspiring perspective on the world and an unforgettable theater experience. Meaningful educational collaborations and partnerships extend each film’s impact far beyond the theater.