A group of explorers from the British Cryptozoological Society goes on an expedition into the Congo in search of a cryptid—the so-called Mokele-mbembe which is believed to be a Plesiosaur called Elasmosaurus. Along with the five explorers are two television cameramen who will be recording the whole expedition. The explorers consist of their leader Jonathan, their medic Liz, their sponsor organiser Charlie, their pilot, and a local guide, named Amara. During the helicopter flight, Johnathan discovers that his son Luke sneaked into the chopper as a stowaway.
Shortly after that, a flock of large flying reptiles (pterosaurs) appears next to the helicopter and one of them crashes into the chopper blades, causing the helicopter to crash. The pilot dies in the crash and everyone else escapes just before the chopper explodes. Now lost, they discover that the satellite phone they had with them was broken during the crash, Amara suggests that they should head to the village they saw while they were in the helicopter. Upon arriving, the group discovers that the villagers have been killed and the village destroyed. Johnathan chooses a hut to stay in for the night and his son, who is technically talented, installs a night vision camera outside the hut.
At night, everyone is woken up by strange noises and Luke sees a swarm of bat-like reptiles outside the hut on the monitor linked to his night vision camera. Charlie accidentally alerts the creatures by making a noise and they try to flee from the village which is infested with the animals. Liz is attacked and killed while the rest escape in a pair of wooden boats and spend the night and part of the day on the river, until they arrive on a tropical island. On that island they encounter a group of dinosaurs with one in particular that seems to like Luke, which he decides to name Crypto. He spits a fluid on Luke. The next morning, they discover that the dinosaurs are still there and Luke decides to attach one of his cameras onto Crypto's neck to see where he would go to. The broadcast cuts out as the dinosaurs swim into a cave.
The group heads back on the river when the broadcast returns and Luke and Charlie see that the dinosaurs went straight to where they originated, some kind of underground gateway, where the camera is dropped. When they try to steer through a whitewater, Luke's and Charlie's boat gets separated and drifts off towards the cave where the dinosaurs went earlier. The rest of the explorers follow them and rejoining them in a river canyon, they encounter a magnificent Elasmosaurus. A suddenly emerging Pliosaur attacks the group. Charlie and Luke get out of the water, believing that the rest of the group died and continue to search for the place where the dinosaurs came from, in the jungle. Eventually they arrive there and when Charlie learns that Luke has fixed the satellite phone, he pushes Luke down into the gateway, intending to kill him.
On the other side of the underground passageway, Luke speaks into the camera, trying to reach the other survivors via the monitor. In the next scene the survivors are seen walking around at the river beach amidst the remains of the boats, the camera monitor lies shattered on the ground. Amara reveals that she was supposed to lead the group to do some records at a safe place in the jungle but she refuses to go towards the gateway and leaves, taking one of the boats. Jonathan and Pete continue the search for Luke and Charlie. In the meantime, Luke meets Crypto and follows him deeper into the jungle, where he is attacked by the bat-like creatures. He is rescued by Pete, who suddenly appears together with Jonathan and drives off the creatures. Pete chases them into the jungle, when he is suddenly encircled by the creatures who attack and presumably kill him. Charlie is seen, speaking to the camera at an unknown place, when he is interrupted and forced to hide by Jonathan and Luke, continuing through the jungle. They follow a steep cliffway, when they are hit by a rockfall, causing Jonathan almost to fall down the cliff. As Luke looks up, Charlie is seen with a stick in his hands, indicating that he caused the rocks to fall. Luke tries to help his father who is holding onto a rock, but, telling him that he loves him, he lets go of the rock and falls down the cliff.
Luke escapes from Charlie and hides in the dense jungle, evading Charlie who is chasing him, when he meets the little dinosaur once more who leads him to the place where he dropped his camera earlier, when suddenly Charlie emerges in front of him, intending to kill him. Crypto spits the fluid into Luke's face, when two adult dinosaurs appear just behind Charlie, sniffing on Luke and smelling the fluid, they leave him alone and kill Charlie.
Luke proceeds into the jungle and stops at a high cliff, filming himself and the little dinosaur, saying that the satellite phone has been crushed again and that he has to destroy the cameras to use the parts, he waves the camera over the view from the cliff, showing a big valley full of dinosaurs. In the next scene he is seen throwing the backpack down a waterfall into a river, as a message. Luke's fate is unknown.
The floating backpack is found by men in a boat, who find video hard drives and tapes labelled "the Dinosaur Project" inside. In a blurry video, Luke says "I think it works".
Dinosaurs and Prehistoric Reptiles[]
- Afrovenator (inaccurately with a frill around its head)
- Anurognathus (batosaurs)
- Elasmosaurus
- Liopleurodon
- Pteranodon