Contains spoilers for this episode and earlier episodes.
Chernobyl's cleanup reaches the emptied villages and the roofs surrounding the destroyed reactor. A young recruit, Pavel, joins veteran Bacho on a patrol ordered to kill animals left behind in the exclusion zone. The pets still approach people or wait in abandoned homes, and Pavel struggles to carry out the order despite Bacho's instructions. Bacho insists that a wounded animal must be killed quickly, and takes over when Pavel cannot shoot a dog with puppies. Elsewhere, an elderly woman refuses an evacuation order until a soldier shoots her cow. The episode also returns to Lyudmilla, whose baby dies shortly after birth.
At the power station, radioactive graphite must be cleared before the reactor can be enclosed. Remote machines handle some sections, but a West German robot fails on the most contaminated roof. Shcherbina discovers that the radiation figures supplied to its makers were false. General Tarakanov therefore sends men out with shovels, limiting each turn to roughly ninety seconds. They hurry across broken debris, push graphite over the edge and scramble back through the doorway. Meanwhile, Khomyuk reconstructs the failed safety test and discovers that information about an earlier reactor incident has been suppressed. Her findings put Legasov under pressure to explain the design problem publicly. As his appearance in Vienna approaches, the scientists face a question the cleanup cannot resolve: whether the state will allow them to tell the truth about what happened.