Starring Koichi Sato and Ken Watanabe, it is about the titular group of employees tasked with handling the meltdown of the Fukushima Daiichi Nuclear Power Plant after the 2011 Tōhoku earthquake and tsunami.

A station blackout (SBO) caused the reactor to fall into an uncoolable situation and suffer unimaginable damage due to nuclear meltdown.

On-site workers, including Izaki Haruka, who is on duty at Units 1 and 2, remain in the nuclear power plant and work hard to control the reactor.

In the worst scenario of this accident estimated by the Kantei, the damage range would have a 250 km radius with the evacuation target population of circa 50 million people, which meant the destruction of eastern Honshu (largest main island).

"[4] The storyline suggesting that the Prime Minister of Japan directly boarded the nuclear power plant and delayed the venting process, leading to an expansion of the damage, is contradicted by the report of the accident investigation committee, which has completely refuted this claim.