《四区四线和三区三线》Setinanuncannyfuture—orperhapsaslightlyalternatepresentwherecellphonetechnologyisnowheretobefound—AnnaandherpartnerRyanhaveachievedeverycouple’sdream:theyareinpossessionofadocumentcertifyingtheirtruelove.Theircomfortableifsomewhatmundanelife,however,leavesAnnaquestioningtheirsuccessfullovetest,administeredbyplacingtheirextractedfingernailsintoacutting-edgemachine.AnnasoonbeginsworkingfortheLoveInstituteunderthetutelageofDuncan(LukeWilson),which,inadditiontodeterminingacouples’statusviathemysterioustest,trainsthemtodeepenbonds.There,she’spairedwiththeexperienced—anddevastatinglycharming—Amirtotakecouplesatvariousstagesofrelationshipsthroughaseriesoflove-buildingactivitiesbeforethebigtest.Asthenewcolleaguesworktoamelioratetheconnectionsofclients,AnnabeginstowonderifperhapsAmirisheronetrueloveandiftrustingherownfeelingsisamorereliablemetricthanwhatisdeterminedbyamachine.