House hunters Gemma and Tom find themselves trapped in the empty cryptic maze of a vast housing development. No matter what corners they turn, they find themselves back where they started. All attempts to escape are futile, so they are forced to take up residence in a sick simulacrum of suburban living. Are Gemma and Tom the subjects of some bizarre experiment? The mockery of family living is stretched to breaking point and the chain of events that follows reveals the horrific truth beneath the Vivarium.