Baboonlizards possess a mandrill-like head and a reptilian body. They are carnivorous and even eat humans, and they possess a highly durable skin, except at their neck. They appear to live and hunt in groups. Like bats, they sleep upside down on ceilings. They also possess a terrifying shriek.
A Sound of Thunder
After the death of a butterly during a Cretaceous safari, the course of time changed and the Baboonlizards appear in the Present.
When the Time Safari employees Travis Ryer, Sonia Rand, Marcus Payne, Dr. Lucas and Jenny Krase start seeking the client which killed the butterfly, they hear the Baboonlizards' shriek in a forest. Suddently, a Baboonlizard comes and kidnaps Lucas, but Travis pursues him and shoots at him with his gun, killing him. Then, a pack of Baboonlizards comes and attacks the group. Marcus, who has been poisoned earlier, decides to sacrifice himself to allow the group to escape. He shoots some Baboonlizards, but he is rapidly surrounded by the pack and devoured alive.
Soon after, two Baboonlizards attack a father and his son in a ruined store. Travis comes and saves them by killing one of the Baboonlizards, though the other survives and leaves.
Later, the group goes back to Time Safari Headquarter, but they discover that several sleeping Baboonlizards are present. They decide to leave and to go to a nearby university, but their colleague Clay Derris who was stayed there tries to follow them and awake the Baboonlizards which devour him.
Finally, Travis and Sonia arrive at the university, but the pack of Baboonlizards follows them. The creatures climb over the walls and enter in the building, then they try to break down the doors of the room where Travis and Sonia are. But when they succeed, Travis travels back into the Cretaceous and changes the course of time, making the Baboonlizards never exist.
- Despite being the main antagonists of the movie, they didn't appear in Ray Bradbury's short story which inspired it.