At the breaking point of their dysfunctional marriage, Cass and Gav take a trip through Serbia. After meeting a mysterious local, Saint Peter, who eagerly offers to be their guide, the couple embarks on an impromptu sightseeing expedition that soon takes a series of sinister turns.

Far away, in the desolate Serbian wilderness, a U.S.-led fracking crew uncover a dormant monster gestating inside a centuries-old French soldier. Now awakened and exposed in its most dangerously fragile state, it tears through the men on the grounds in search of a new womb.