They Nest

A skilled doctor stressed by a marital breakdown and alcohol problems, Cahill retreats to Orr Island to decompress. He applies scientific methods to investigate the mysterious insect-infected corpses and becomes the town's reluctant investigator. As mob fear rises, he fights to prove the threat is real while grappling with personal turmoil.

The local lawman tasked with keeping order as the outbreak unfolds. He confronts rising violence and is ultimately overwhelmed by the scale of the threat. His attempts to protect Cahill and the community falter as the insects claim him.

A desperate man who breaks into Cahill's home and is killed by the cockroaches. His intrusion sets off early tension in the town and foreshadows the danger the inhabitants face. His actions catalyze the community's shift from suspicion to alarm.

Jack's brother, involved in the violence against Cahill and the town's attempts to quell the outbreak. He is ultimately killed by the insects, symbolizing how the infestation destroys both people and social order.

Cahill's partner who becomes a key ally in evacuating townsfolk and supporting his fight against the invasion. She endures jail with Cahill and stands by him as the situation spirals.

A local resident who joins the effort to protect the town, attempting to help release authorities and aid the evacuation. He represents the community’s willingness to act under pressure.

A fellow doctor who contributes to the scientific response, assisting Cahill as they investigate the mutations and spread of the infestation. His role underscores the collaborative effort of medical professionals.