Three years after being kicked out of the science department for his theory of Time warps, Rick Marshall is reduced to working as a teacher at the George C. Page Museum. He meets Holly Cantrell whose finding urges him to create a tachyon amplifier to enable time warp travel. Once they activate the amplifier, Rick, Holly and their cave tour guide Will Stanton end up in a parallel universe where all timelines converge. They soon meet some ape men and Stanton unintentionally gives them the secret of fire. A T. rex chases them across a small land bridge. Holly disappears and is condemned to death by the Library of Skulls. They finally make it back to the right time and bring back a dinosaur egg to prove his theory.