In the final season of Homeland, Carrie Matheson, who has endured more than seven months of brutal imprisonment in Russia, is gradually recovering, but her memories are still fragmented, which is a problem for Saul Berenson. As the national security adviser to the newly elected US President Ralph Warner, he was sent to Afghanistan to negotiate with the Taliban, but Kabul is full of warlords, mercenaries, fanatics and spies - this forced Saul to seek help from Carrie, who is familiar with the place, and begged her to accompany him to the tiger's den for the last time despite the doctor's advice.