An Open Door (ヒラカレタトビラ, Hirakareta Tobira) is the fourth episode in Japan Sinks: 2020.
An arrow hits Go Mutoh and Kite quickly comes to perform first aid, but they see Go is fine and the arrow hit his game console. The store owner comes out and apologizes, stating that he didn't intend to hit anyone and tells them they can stay inside as storm is coming. The man takes the broken console and later fixes it. The group sits around a table and eat dinner and seeing the rain Go and Ayumu wonder if they can take a shower in the rain, but Kite tells them its dangerous as he saw nuclear power station in smokes and shows readings on his phone for higher radiation levels.
In the morning, Kite wakes them and says that the building is tilted at 7 degrees and explains its not just the building, but the whole Japanese archipelago is leaning towards the Pacific Ocean. As they prepare to leave, an earthquake occurs and they take the store owners truck and leave. As they run, he tells them about safe place, Shen City, as they watch as they watch the road and the store collapsing behind them. Due to the road ahead being destroyed, they are forced to take a detour and later stop for the night. The next day, they find a hitchhiker, Daniel, and take him with them, although the store owner was against it as he hates foreigners. That night they reach Shan City, which is surrounded by a fence and has cameras. They are welcomed inside, letting them shower and later are given curry for dinner. Go comment he doesn't like it, as it contains vegetables and he doesn't like them, but Haruo comments its just like his mother's and recalls how she was crushed during the earthquake.
Osamu shows the group around, explaining how they are self-sustaining and that they are welcomed to stay as long as they want. Osamu then shows them tends where they can spend the night. Kite visits the store owner and gives him morphine, realizing its what he wanted. He takes it gladly, but explains he is there for another reason.
In the morning, a woman exercise after taking a bath and a man reminds her its time to meet the dead.