The story follows "The Purge 3". Adela and her husband Juan, who escaped from the drug cartel, came to Texas from Mexico, and the latter worked on the Tucker family's ranch. Juan was highly appreciated by Caleb, the patriarch of the Tucker family, but this also made Caleb's son Dylan jealous. But on the morning after the annual "Purge", an underground organization intended to continue the killing, causing chaos across the United States. The Tucker family, including Dylan's wife and sister, were also affected, forcing everyone to unite to deal with the mob and try to escape to Mexico, which opened its border for only six hours.