Unable to bear his noisy neighbors, Lin An adopts a stray kitten named Tuanzi. The little cat quickly grows into a gigantic prehistoric saber-toothed tiger. The research institute initially intends to take it over, but the giant beast only feels close to Lin An, so they specially hire him as its caretaker and the two move to an estate in the valley. After Tuanzi consumes crystals and awakens special abilities, it attracts the greed of unscrupulous corporations. Together, the man and beast overcome various provocations, explore ancient ruins, and fight mutated creatures and criminals. The schemers end up disgraced, an ecological conservation base is established, and Lin An and his saber-toothed tiger companion protect ancient life together, writing a heartwarming story of coexistence.