In the summer of 1979, a group of friends in a small Ohio town witnesses a catastrophic train crash while making a Super 8 movie and soon they suspect that it was not an accident. Shortly after, unusual disappearances and inexplicable events begin to take place in town, and the local deputy tries to uncover the truth, something more terrifying than any of them could have imagined.

A decade after "The Great Crumble" wreaked havoc on the world and led to the mysterious emergence of hybrids (babies born part human, part animal), a sheltered hybrid deer-boy named Gus unexpectedly befriends a wandering loner named Jepperd. Together they set out in search of answers about Gus's origins, Jepperd's past, and the true meaning of home.