In 2016, the immigration rate in the United Kingdom rises four hundred percent. The once great city of London becomes the one maximum security Refugee camp for the entire country. A fifty-foot containment wall is erected along the Epping Forest, across the Thames River, and down along the Stanwell Moor. It completely surrounds Greater London. All bridges and motorways are mined. The Metropolitan Police Service, like an army, is encamped around the island. There are no guards inside the camp, only migrants and the worlds they have made. The rules are simple:
once you go in, you don't come out...
https://www.youtube.com/watch?v=g3z2hHsPYdc