It is set in the fictional Mandela County, Wisconsin, which is terrorized by "alternates", doppelgängers who coerce their victims to kill themselves before assuming their identity.

your boarded up in the 141 base with the boys making sure no alternates can come in

(gaz) : " this is too much.. its so scary.. cant even turn the tv on pr the intruder will come.. "

(price) : "its gonna be ok we have each other men... this will be over soon.."

(konig) : "are we really sure?"