Craig Mazin

Legasov records his final testimony, reflecting on the systemic deception and the true cost of the nuclear disaster before his suicide.

Charkov offers Legasov high honors in exchange for his cooperation at the upcoming trial, while Legasov pushes for the safety of the reactors.

Legasov desperately tries to convince Shcherbina of the unprecedented scale of the disaster while proposing a dangerous plan to smother the core.

Ellie reads a poignant farewell letter from Bill to Joel, reflecting on the purpose of survival and the importance of protecting those they love.

Ulana Khomyuk uses coded language to confirm the severity of the reactor fire with a colleague before deciding to travel to the disaster site.

Khomyuk and Shcherbina debate whether Legasov should expose the Soviet Union's nuclear flaws in Vienna or make a dangerous deal with the KGB.

Legasov explains the gruesome biological effects of radiation poisoning to Shcherbina as they realize the fatal cost of their mission.

Frank, who is terminally ill, asks his partner Bill to help him end his life after one final perfect day together. He outlines a plan for their last hours, emphasizing his love and the peace he seeks in Bill's arms.

Joel establishes strict ground rules for their journey, demanding that Ellie keep her condition a secret and never mention his late partner, Tess.

A high-ranking Soviet official intimidates a scientist into explaining nuclear physics under the threat of being thrown from a helicopter.

Charkov confronts Legasov with his past compromises, stripping him of his dignity and legacy as punishment for telling the truth about the disaster.

Legasov risks his life by testifying against the Soviet State, exposing the systemic lies and design flaws that caused the nuclear disaster.

Valery Legasov records a final testament reflecting on the objective nature of truth and the dangerous naivety of the scientific community.

A nurse confronts a grieving wife who has stayed past her visitation time, warning her that her husband's radiation poisoning makes him a lethal threat.

Ulana Khomyuk confronts Valery Legasov with a terrifying realization: the melting reactor core is about to cause a massive steam explosion.

Joel returns home from work to a surprise birthday gift from his daughter, Sarah, and they share a tender moment. Later that night, a phone call from Joel's brother, Tommy, is cut short, and Sarah discovers a terrifying nationwide pandemic unfolding, forcing Joel to protect her from an infected neighbor.

Legasov tasks Khomyuk with a dangerous investigation into the reactor's failure, warning that the truth must be found before the witnesses die.

Valery Legasov delivers a sobering briefing on the catastrophic environmental cleanup and the inevitable human cost required to contain the radiation.

Shcherbina testifies at the trial, explaining the fatal flaws in the reactor's safety protocols and the history of failed tests leading to the disaster.

Facing their terminal radiation sickness, Shcherbina laments his wasted life as a bureaucrat while Legasov insists he was the only one who mattered.

Bacho introduces a young recruit to the grim reality of liquidator work, explaining their task of culling radioactive pets in the exclusion zone.

An elderly official demands total loyalty to the State, ordering a city-wide lockdown to contain information following a nuclear disaster.

Khomyuk reveals a terrifying inconsistency in the plant operators' accounts, forcing Legasov to confront a potential flaw in the Soviet reactor.

Legasov confronts the KGB Deputy Chairman about an associate's arrest, facing a chilling display of bureaucratic power and surveillance.

Khomyuk visits a dying Dyatlov in the hospital to uncover the technical truth behind the reactor's explosion. She confronts him with evidence of state-redacted documents, while Dyatlov remains cynical and defensive about his impending execution.

Legasov warns Shcherbina about the fatal radiation levels in Pripyat while the Soviet government realizes the disaster is no longer a secret.

Legasov uses a chilling metaphor to explain the catastrophic scale of the radiation leak to a room of skeptical Soviet officials.

A young soldier attempts to evacuate an elderly woman from her home following the Chernobyl disaster. The woman refuses to leave, recounting the century of war, famine, and revolution she has survived, arguing that she will not flee from an invisible threat like radiation.

Khomyuk pressures Legasov to use his testimony at the show trial to expose the truth to their colleagues and force systemic reform.

A seasoned veteran explains the grim reality of the radiation safety protocols to a naive new recruit. He reveals that the official measurements are falsified to keep men working in the disaster zone, highlighting the systemic negligence and the expendability of the liquidators.

Bacho attempts to comfort a young recruit who is struggling with the emotional weight of his first kill during the liquidator operations. He shares a grim story from his time in Afghanistan to illustrate the hardening of one's soul in the face of duty.

Valery Legasov explains the complex physics of a nuclear reactor to a courtroom, detailing the fatal imbalance that led to the disaster.

Frank and Bill argue over the maintenance of their home and the possibility of inviting outsiders into their isolated sanctuary.

Joel and Tess, smugglers in a post-apocalyptic world, discuss a botched deal and Tess's injuries. They discover their associate, Robert, has double-crossed them and set out to find him before a rival group, the Fireflies, does.

Boris Shcherbina calls Valery Legasov to inform him of an accident at the Chernobyl Nuclear Power Plant. While Shcherbina attempts to downplay the severity of the situation, Legasov immediately recognizes the danger of the reported radiation levels, leading to a tense exchange about authority and expertise.

A younger doctor questions a senior colleague about iodine supplies as news of a fire at the power plant begins to surface.

While trekking through the woods, Ellie questions Joel about how the world collapsed and the scientific origins of the fungal pandemic.

In a Moscow hospital, a dying firefighter and his pregnant wife share a tender, tragic moment as he fulfills a promise to show her the city.