The planet LV-363 teems with exotic life, including a plant growing in the shadows of its deep rifts. The plant's flower yields a valuable narcotic, and people are forced by the cartels to harvest it.

When a Yautja (Predator) ship arrives for a hunting ritual, the Predators seed the rifts with Xenomorph eggs. The aliens emerge and the result is bizarre and deadly hybrids, with humans trapped between the Predators and their prey. These deadly Xenomorph hybrids--some of which possess the ability to fly--swarm out of control and may prove more than either the Yautja or the humans can defeat.