In 2025, a trial run of Nankai MER has begun. The Nankai MER (Mobile Emergency Room) travels arounds islands in the southern sea on a ferry and carries the special vehicle NK1 that is equipped with an operating room. Doctor Kitami Kota and Nurse Kuramae Natsume, who are both from Tokyo MER, are assigned to Nankai MER. One day, a large eruption suddenly occurs on Suwanosejima Island in Kagoshima. Hot lava runs down to villages and flying volcanic rocks destroy everything in its path. Due to smoke from the volcano, rescue by helicopter is impossible. In this desperate situation, Nankai MER is challenged to rescue 79 people stranded on the island. (Source: AsianWiki)