The fifth and final episode of the HBO miniseries Chernobyl.
April 1986. It's a normal enough morning in the town of Pripyat. Yuvchenko is playing with his son. Sitnikov is outside with his wife and daughter. Dr. Zinchenko is enjoying a swim. Vasily and Lyudmilla Ignatenko are out shopping and talking to some neighbors. And among all of this, Dyatlov is on his way to work. In Bryukhanov's office, Fomin confides in Dyatlov that their boss is in line for a big promotion which will likely lead to them in turn getting promotions — just so long as Dyatlov successfully completes the safety test scheduled for that afternoon. An irate Bryukhanov then arrives in the office and complains that the grid controller in Kyiv has forbidden Reactor 4 from being fully reduced to the 700MW power level required for the test until the end of the day, in order to ensure that monthly productivity quotas are met. Fomin reassures him that's it's not a problem, and that they can keep the reactor at half power, 1,600MW, until that night. Dyatlov leaves to get some sleep ahead of the now-rescheduled test, while Bryukhanov excuses himself, leaving Fomin to admire the office he believes will soon be his. None of the three men are aware that they've just set off the chain of Disaster Dominoes that will lead to the worst nuclear accident in history.
March 1987. As he buys a pack of cigarettes, Legasov, whose health is already starting to visibly deteriorate, is called into a nearby car. Its occupant turns out to be Charkov, who congratulates him on his recent speech to Vienna, and tells him that Gorbachev intends to reward him with the Soviet Union's highest honor, the Hero of the Soviet Union — on the condition that he maintains the narrative that the accident was purely the fault of Dyatlov, Bryukhanov, and Fomin at their upcoming trial. After Legasov returns home, he's visited by Khomyuk, who reveals that several members of the Soviet scientific community will be present at the trial, and demands that Legasov lay clear the full extent of the flaws in the RBMK design. Legasov is conflicted, sure that there will be dire consequences if he does so, but also having gotten no reassurances from Charkov in their meeting that anything would be done to fix the remaining reactors, on top of knowing that he won't live long enough to enjoy his new honor for more than a few years.
July 1987. The trial of Anatoly Dyatlov, Viktor Bryukhanov, and Nikolai Fomin is convened in the abandoned town of Chernobyl. Scherbina is first to give testimony, and he explains the need for the safety test that was carried out on that fateful night 15 months prior. The RBMK reactor is dependent on external power to run its cooling systems, and in the event of the power failing, it would take a minute for the backup power generators to fully kick in, potentially leading to a meltdown. To prevent this, the operators are supposed to divert power from the turbine to run the cooling systems until the backup generators can kick in, and this test has to be completed before the reactor can go on-line. Bryukhanov, Dyatlov, and Fomin in fact never carried out the test before the reactor went on-line in 1983, but falsely claimed that they had, so that they could get state honors and cash bonuses. The three times they tried it all ended in failure, and the fourth time was on April 26, 1986.
Khomyuk then takes over the testimony, and reveals that the test was meant to take place during the afternoon of April 25, and should have been scrapped entirely when the grid controller refused to allow it to take place as planned, but that the management decided to instead hold it that night. This resulted in the day shift, who had been trained to carry out the test, being replaced by the night shift.
April 1986. Toptunov arrives for his usual night shift at Reactor 4, and is quickly called into the control room, where Akimov briefs him on the test that's meant to be taking place. However, the two men are confused by the instructions, half of which are crossed out. Akimov calls the staff in Reactor 3, who advise him to still follow the crossed-out instructions. Dyatlov then arrives and, after taking a moment to chew out turbine engineer Igor Kirschenbaum for not having read up on a test he wasn't expecting to carry out until moments beforehand, instructs Toptunov to bring the reactor down to the required 700MW.
July 1987. Khomyuk likens the situation that Toptunov was in to Yuri Gagarin having been forced to undertake his mission into space with minimal training, no prior warning, and only a list of half-crossed-out instructions to guide him. She adds that the bigger consequence of the delay was a "poison" building up in the reactor core.
Legasov is next to testify, and explains how the reactor works under normal conditions, with the reactivity balanced by various factors, chiefly the control rods and level of cooling water in the reactor. He also emphasizes the RBMK's positive void coefficient, meaning that as the cooling water boils away, it causes a positive feedback effect that further increases the reactor's power, the opposite of how most nuclear reactors are designed. In the case of Reactor 4 on that night, the balance had been disrupted in the other direction by a build-up of xenon during the hours it had been operating at half-power.
April 1986. Toptunov is bringing the power down to the required 700MW, at a slower pace than Dyatlov would like, when the power level suddenly drops to 500MW without any warning, despite Toptunov not operating the control rods at that moment. Akimov realizes that the core is being poisoned by a xenon build-up, and requests Dyatlov's permission to disable the reactor's automatic regulation systems for long enough to bring it back up to power. Dyatlov agrees, but when Akimov and Toptunov disable the automatic system, it has the opposite effect of what was intended and causes the power to completely crater, ending up at just 30MW. Dyatlov is absolutely infuriated, and despite Akimov's pleading that the safety regulations require a complete shutdown and 24-hour wait for the xenon to decay away, Dyatlov orders him and Toptunov to get the power back to 700MW by any means necessary, threatening to have them Reassigned to Antarctica if they fail.
July 1987. Dyatlov suddenly interrupts Legasov's testimony to claim that he wasn't in the control room at that time, and that Akimov and Toptunov started raising the power of their own accord. This only serves to irk the prosecutor, Stepashin, who points out that both of the deceased men testified to the contrary. Scherbina then suffers a coughing fit, and the presiding judge decides that this is as good of a time as any for a recess. Outside, Scherbina fills in Legasov on the history of the town of Chernobyl, noting that its population was previously all but wiped out during World War II, but that people came back to live in the town anyway, until their blundering around with atomic energy rendered the town permanently uninhabitable. Scherbina then confides in Legasov that his own health situation is similarly grim, if not more so, and that he'll be lucky to be alive by the end of the following year. Succumbing to despair, Scherbina laments that his life and career never amounted to much, but Legasov reassures him that couldn't be any further than the truth; everything that was needed to contain the disaster was obtained through Scherbina, meaning that he saved far more lives than either one of them will ever know.
When the proceedings resume, Legasov tells the court that the xenon levels in the reactor core were too strong for there to be any easy, let alone safe way of raising the power level. The only thing that Akimov and Toptunov could do was start removing the control rods, ultimately leading to them removing all but six of the reactor's 211 control rods.
April 1986. Despite their best efforts, Akimov and Toptunov can only get the reactor up to 200MW. Dyatlov figures this is good enough, despite it being less than a third of what the test requires, and Akimov's protests that the steam levels and turbine speed are both too low for the test to deliver any valid results. By now, Stolyarchuk and Kirschenbaum are similarly convinced that what they're doing is extremely dangerous, but Dyatlov doesn't want to know, and orders them to get things ready for the test. The reactor's SKALA monitoring system prints out a report, warning them that too few control rods are in the reactor and that they should shut down immediately, which is similarly blown off by Dyatlov. Finally, Dyatlov orders the test to begin, shutting off the supply of fresh cooling water. The remaining water begins to boil, at which point the reactor's positive void coefficient kicks in, burning up the xenon which had been slowing down the reaction, and causing the reactor's power to spike fivefold within a matter of seconds.
July 1987. Legasov begins to describe the function of the AZ-5 button, which fully inserts all the control rods at once. He pauses, pondering whether or not to reveal the full truth behind the disaster, but before he can do so, Dyatlov interjects and calls the trial a sham, accusing Legasov and Khomyuk of both spinning lies to convict him and his two co-defendants, neither of whom is very grateful for his input. The presiding judge decides that Dyatlov's outburst is as good as a confession, and announces that no further testimony from Legasov will be required. Scherbina then speaks up and demands that Legasov be allowed to continue, which the judge reluctantly permits. Legasov says that Dyatlov broke every rule in the book and pushed Reactor 4 to the point of self-destruction, but that he did so under the belief that the AZ-5 button would prevent disaster. Unbeknownst to him and the reactor's operators, however, there was a fatal flaw in the system, namely the graphite tips of the control rods, which accelerate the reaction before it's stopped. Upon being asked why the control rods were designed this way, Legasov bluntly responds that it's for the same reason the Soviet Union is the only country to build and operate a reactor as poorly-designed and lethally dangerous as the RBMK — it's cheaper. The court attendees are simultaneously irked by this insult to their national pride, and alarmed at the implications of exactly what unfolded that night.
April 1986. Akimov reacts to the power spike by hitting the AZ-5 button, beginning the insertion of all the control rods into the reactor. The already-accelerated reaction rate further increases, instantly vaporizing all the cooling water in the reactor. The increase in steam pressure damages the fuel rod mechanism and locks the graphite tips in place, which combine with the positive void coefficient to begin a colossal chain reaction, ripping the fuel channels apart, releasing more energy, and increasing the steam pressure to unimaginable levels. Perevozchenko, in the reactor hall, sees the fuel caps — each of which weighs the same as three large men — jumping up and down, and flees in a fruitless attempt to warn the control room of the impending disaster. Khodemchuk and Degtaryenko watch as the pumps begin to burst open from the overpressure, but have no chance of avoiding the blast that will imminently claim both their lives. The control room staffers, meanwhile watch in astonishment as the power spikes to 33,000MW, over ten times what it was designed to operate at, and likely a mere fraction of the actual power output. Finally, the steam overpressure blows the lid off the core, and the inrush of oxygen combines with hydrogen, superheated graphite, and the remains of the fuel rods to produce a titanic explosion which utterly destroys the reactor and most of the surrounding building, scattering chunks of graphite and fuel rod around the immediate vicinity.
July 1987. As the court digests the full truth of what happened, Legasov re-iterates that for as reckless as Dyatlov's actions were, he would probably never have undertaken them had he known of the flaw in the AZ-5 system. The judge reminds Legasov that this contradicts what he said in Vienna, to which Legasov admits frankly that his testimony was a lie — and indeed, that the entire disaster was the result of secrecy and lies, bourne out of a desire to avoid the Soviet Union's nuclear technologies being seen as anything other than the best in the world, even if it comes at the cost of people's lives. He concludes his testimony by saying "That is how an RBMK reactor core explodes. Lies."
Legasov is immediately taken from the courtroom to a bathroom, where he's eventually confronted by the enraged Charkov, who threatens him with the death penalty. Charkov then admits that they can't actually punish Legasov in any real way, as his appearance in Vienna would lead to too many questions if he suddenly disappeared. Instead, his testimony at the trial will be disavowed and kept secret, he will hold his job in name only and not be permitted any actual duties, and the history books will be rewritten to give credit for his accomplishments to other people. Charkov demands to know whether Scherbina or Khomyuk were complicit in Legasov's actions; Legasov denies it, which Charkov doesn't believe for a second, but it doesn't make much difference, seeing how Legasov and Scherbina will soon be dead anyway, and Khomyuk already has too much of a reputation as a troublemaker to advance far up the career ladder. Legasov is told that he will spend the rest of his life in seclusion, with the implication of dire consequences for himself, Scherbina, and/or Khomyuk if he ever communicates with them in any way again — and, for that matter, anyone else he tries to tell the truth of Chernobyl to. Legasov asks what will happen if he refuses, but Charkov tells him not to worry about something that's never going to happen. "That's perfect. They should put that on our money." snarks Legasov.
As he's led away to begin his life of isolation and ignominy, Legasov shares one last look with Scherbina and Khomyuk, knowing that they at least tried to do the right thing, and hoping that it will somehow, someday pay off. An except from Legasov's tape recording plays us out:
Preceded by "The Happiness of All Mankind".
Tropes:
- Accidental Truth: Dyatlov calls Legasov a liar during the trial in a futile attempt to deflect fault from himself. As it turns out, Legasov has lied at Vienna (and for years before Chernobyl) by order of the KGB.
- All for Nothing: Subverted. Shcherbina, now diagnosed with terminal cancer, muses to Legasov how he has spent his entire life working for the government only to be sent to certain death in the end. He laments that he is an "inconsequential man" whose life was wasted in the pursuit of self-importance. Legasov rebuffs him, pointing out that no one else could have directed the clean up, rallied the troops, or acquired all the resources that made the operation possible as well as Shcherbina. Far from it, Shcherbina's actions ended being just as important, if not more so, than any of the scientists or workers. He really did matter in the end.Legasov: There are other scientists like me. Any one of them could have done what I did. But you . . . everything we asked for, everything we needed; men, material, lunar rovers. Who else could have done these things? They heard me, but they listened to you. Of all the ministers and all the deputies. Entire congregation of obedient fools, they mistakenly sent the one good man. For God's sake Boris, you were the one who mattered the most.
- Already the Case: After Legasov reveals the reactors' design flaw, the judge presiding over the trial warns him that by accusing the state of such a grave error he is "treading on dangerous" ground. Legasov responds, "I've already trod on dangerous ground. We're on dangerous ground right now!" acknowledging that he knows he has already said too much and reminding the court that the very ground they're on has been lethally contaminated by the consequence of the state's negligence.
- Appeal to Authority: One of Dyatlov's trademark bully tactics during the lethally unsafe test is to constantly appeal to his title and years on the job when his subordinates protest that he's breaking every safety procedure they have.
- Armour Piercing Response: After being asked by the judge why the reactors have a fatal design flaw, Legasov states it's the same reason why the entire soviet nuclear plan has other serious flaws that he lists and then:Legasov: It's cheaper.
- As You Know:
- When Legasov is offered a Hero of the Soviet Union award, Charkov feels obligated to say that it's the USSR's highest honor.
- Later, Charkov mentions how Legasov was a member of the Komsomol, then helpfully tells the audience that the Komsomol is the "Communist Youth".
- Audience Murmurs: There are several times during the trial when the scientists in attendance are shown reacting to Legasov's testimony. After he reveals that the control rod tips are made of reaction-accelerating graphite, they are shown worriedly murmuring amongst themselves.
- Bad Boss: The sheer extent of Dyatlov's downright abuse of his subordinates is revealed in this episode, and their reluctance to work under his supervision suggests it's typical of his behavior. Throughout the preparation for the test he insults and belittles them, begins shouting spontaneously, throws things at them, and threatens to have them blacklisted from work in their fields when they question his orders. It's a wonder the reactor doesn't explode on its own from sheer stress.
- Bastardly Speech: When bullying his men into carrying out a blatantly unsafe procedure, Dyatlov delivers a little speech about how he has always preached "Safety First".
- Bavarian Fire Drill: Played With. According to Khomyuk's testimony at the state trial, the "first link in the chain of disaster" that led to the explosion was the decision to postpone the safety test for ten hours - causing it to be performed by the inexperienced night shift crew, with an underpowered reactor already poisoned by xenon - because the power grid supervisor refused to allow a further reduction in electrical output during the day. In the opening flashback, Bryukhanov informs Fomin and Dyatlov of the delay, and Fomin starts to object that the grid supervisor doesn't have the authority to make that decision. Bryukhanov shuts him down fast, reasoning that the grid supervisor could only have made the decision if someone higher up the ladder had made it first, which means the last thing they want to do is question it and antagonize that someone.
- Beyond the Impossible: Perevozchenko sees the 350 kg (771 pound) caps on top of the reactor lid being lifted by sheer steam pressure right before the explosion blasts the 2,000 ton lid 30 meters into the air. Khomyuk refers to this as "see[ing] the impossible."
- The Big Board: At the trial, Legasov uses blue and red tiles on a shelf to represent the different factors in how a nuclear reaction is controlled.
- Big Red Button: The AZ-5 button, which was supposed to initiate an emergency shutdown, is depicted as a large red button covered with a safety cover. Due to gross negligence during the safety test procedure and a fatal design flaw in the reactor core rods, instead of shutting the reactor down pressing it causes the core to explode.
- Bittersweet Ending: The disaster is contained, but at great cost in human life. The surrounding area is an irradiated no-man's land, though life is slowly creeping back into the area. Steps are taken to prevent another such disaster happening again, but Legasov is forced into social isolation for speaking out and commits suicide two years after the disaster. However, his martyrdom spurs the Soviet nuclear industry to correct the dangerous flaws in the RBMK reactor design. Shcherbina dies within five years of the disaster, just as predicted. According to the epilogue, The people of Pripyat and the surrounding evacuated areas were able to move on and start new lives, and Lyudmilla even had a son despite being deemed infertile, while Gorbachev believed that the disaster led to the collapse of the Soviet Union.
- Blatant Lies: Dyatlov lies through his teeth and says he wasn't even in the control room when the power was raised, he was in the men's room. Legasov and the prosecutor both shut him down instantly.
- Bookends:
- The series begins and ends with the same line from Legasov's recorded memoirs: "What is the cost of lies?"
- In the last episode, Legasov finally answers the other Driving Question posed in the first episode: How does an RBMK reactor explode?
- Butterfly of Death and Rebirth: Shcherbina notices a small green inchworm in the exclusion zone, showing that life has not been completely eradicated, immediately following him talking about his own impending death.
- Color-Coded for Your Convenience: At the trial, Legasov uses red and blue tiles to illustrate his explanation of how nuclear reactors stay balanced (or, in this case, don't). The red ones represent factors that increase reactivity, while the blue ones are for factors that decrease it. The cards are all labeled, but in Cyrillic like all writing in the show—the creator remarks on the podcast that it doesn't matter because the colors tell the audience all they need to know.
- Composite Character: The epilogue clarifies that the character Ulana Khomyuk was created to represent the dozens of scientists who assisted Legasov after the disaster.
- Confess to a Lesser Crime: We find out at the beginning of the episode that Legasov has explained to the international conference in Vienna how human error contributed to the accident, while concealing the deadly design flaw of the reactors. Just as the Kremlin intended, the conference was satisfied by this confession and praised Legasov as a rare "Soviet scientist who tells the truth".
- Convenient Terminal Illness: Legasov is ultimately willing to say things in court that will endanger his life because he knows he is dying anyway.
- Courtroom Episode: A large portion of the episode is about the trial of the three main plant managers responsible for the disastrous test.
- Cutting Corners:
- As Legasov reveals at the trial, the fatal flaw in RBMK reactors was the result of this.Legasov: These [control] rods are made of boron—which reduces reactivity—but not their tips. The tips are made of graphite, which accelerates reactivity.
Judge: Why?
Legasov: Why? For the same reason our reactors do not have containment buildings around them, like those in the West. For the same reason we don't use properly enriched fuel in our cores. For the same reason we are the only nation that builds water-cooled, graphite-moderated reactors with a positive void coefficient.[beat] It's cheaper. - Shcherbina also states that the plant was completed at the end of a fiscal year, so that the manager could get a bonus. Naturally, not all procedures were completed.
- As Legasov reveals at the trial, the fatal flaw in RBMK reactors was the result of this.
- Derelict Graveyard: As Shcherbina and Legasov are driven to the trial in Chernobyl, they pass by a yard that contains all of the vehicles that were utilized in the cleanup. Cars, trucks, buses, water tankers, APCs, gunships, cargo helicopters, all of them can never be used again because of all the radiation they absorbed.
- Description Porn: Much of the episode consists of the three protagonists explaining in moment-by-moment detail just how and why the reactor exploded, under the assumption that by now the audience will be sufficiently invested in the mystery to enjoy the description. It's helped along by flashbacks to the events being described.
- Disaster Dominoes: With their testimonies at the trial, Shcherbina, Khomyuk, and Legasov detail all the factors that went into the accident—human, scientific, and political.
- Don't Create a Martyr: Legasov isn't killed or punished in a way that would make it obvious he is punished because he has already become famous in the outside world for his testimony in Austria; it would be "embarrassing" and make him a martyr if anything was done to him. Which is exactly what happens after his suicide.
- Double Meaning: In the flashbacks to the night of the explosion, Dyatlov remarks, "In a few minutes, this will all be over," meaning the test will be finished, but unknowingly foreshadowing the imminent disaster.
- Double-Meaning Title: "Vichnaya Pamyat" (Ukrainian for "Memory Eternal") is an exclamation said at the end of Eastern Orthodox funerals. It stands both for the In Memoriam to the people involved in the disaster at the end of the episode, and for Shcherbina and Legasov's enduring legacy despite the KGB's attempt to unperson them.
- Eldritch Abomination: The slow-motion shot of the core exploding, tangled mass of graphite rods emerging from the ground
, looks like some sort of tentacled monster emerging from the depths. It even fulfills the nature of these monsters by being fatal to anyone that just gets in its vicinity, let alone anyone who actually sees it. - Epic Fail: Naturally, the RBMK reactor safety test on April 26, 1986, counts as one. It was actually the fourth time they'd attempted the test over three years. No one suspected such a simple test could cause such a massive disaster—and it wouldn't have, if everything else hadn't already gone wrong. Shcherbina delivers an epic condemnation of the power plant's management in the trial:Shcherbina: The first time they tried it, they failed. The second time they tried it, they failed. The THIRD time they tried it, they failed. The fourth time they tried it... was April 26, 1986.
- Epilogue Letter: The series ends with a passage of Legasov's tape recordings which he left before committing suicide, followed by a Real-Person Epilogue.
- Ethereal Choir: The music during the Real-Person Epilogue.
- Failsafe Failure:
- During the trial, Shcherbina explains that the reactor has three diesel-fuel backup generators to provide power to the pumps in the event that the power to the plant itself is disrupted. However, they take one minute to be brought up to speed, which would have been enough for a nuclear disaster. Such a serious design flaw was what necessitated the safety test in the first place.
- As Legasov eventually reveals, the AZ-5 system that should have safely shut down the reactor had a fatal flaw none of the crew had been made aware of: the control rods were tipped with graphite which briefly caused a power-spike when engaged. Using them on a reactor that was already experiencing a runaway reaction caused the rods to fail and triggered the explosion..
- Flashback: The episode begins with a series of scenes 12 hours before the explosion, showing the plant official scheming about the safety test and Lyudmilla gazing fondly at her husband interacting with their neighbor's baby. During the trial, the witnesses' testimonies are interspersed with further flashback scenes showing the immediate buildup to the disaster.
- For Want Of A Nail: Chernobyl is ready to conduct the safety test during the day shift, whose technicians had been trained to run it. Then a grid controller in Kiev asks them to keep running for an additional ten hours to satisfy evening demand.note Both Fomin and Dyatlov agree that they can afford a ten-hour delay.
- Foreign Language Title: "Vichnaya Pamyat" is Ukrainian for "Memory Eternal".
- Four Is Death:
- The safety test that caused the explosion was the fourth attempt to finish the test, occurred in Reactor 4, and happened during the fourth month of the year.
- Shcherbina ended up dying four years and four months after he was sent to Chernobyl.
- The Greatest Story Never Told: Charkov tells Legasov that his efforts will be hidden from the public and the credit given to other people. While the exact circumstance that leads up to this is fictional, he was indeed largely erased from the story until his death, as a combination of backlash for speaking out against the Soviet government and criticism from other scientists who thought him a Know-Nothing Know-It-All whose decisions like dumping sand and boron on the open reactor just made things worse.
- Hate Sink: Deconstructed regarding Dyatlov. Legasov points out that while man certainly bears a lot of responsibility for the accident, the sheer volume of hatred being directed at him is distracting people from the numerous lies and cover-ups (many of which Dyatlov wasn't even aware of) that made the situation so dangerous.
- Hell Is That Noise: The repeated clanging of the control rod caps which make up the cover of the reactor, as they're forced partially out of their mountings by the rising steam pressure. 350 kg (771 pounds) hunks of metal aren't supposed to just start jumping up and down like that.
- Hoist by His Own Petard:
- The control rods and AZ-5, meant to act as the ultimate failsafe should the reactor spin out of control, end up being the final nail in its coffin due to their graphite tips accelerating the reaction before the boron segments can touch the core. Once the accelerated core flashes all the remaining water to steam, the resultant pressure cracks the lowering mechanism, jamming the rods with only the graphite tips touching the core, creating a snowball effect that blows the lid off the reactor, allowing oxygen in that then ultimately causes the final explosion.
- In a political sense, Legasov seems reluctantly willing to accept hiding the known failure of the cooling rod design so long as the government makes good on its promise to fix them in the other nuclear power stations. When it becomes clear that they have no intent to actually follow through on correcting them for fear it could expose their cover-up, he spills the whole truth at the trial.
- Hope Sprouts Eternal: Shcherbina finds a green inchworm living in Chernobyl one year after the accident, representing the beauty of life and how it will always find a way to survive. Animals in the Exclusion zone aren't too different save for a shorter lifespan.
- How We Got Here: The first episode begins with the explosion of Reactor Number Four and its immediate aftermath. This episode is an excruciating, moment-by-moment lead-up to the explosion, beginning with the fateful meeting between Bryukhanov, Fomin, and Dyatlov. After four episodes of seeing the accident's terrible cost, the audience is practically screaming at the night shift crew not to listen to Dyatlov's idiotic orders.
- I Lied: At the trial, Legasov is asked why his testimony, which featured Brutal Honesty about the reactor's glaring design flaws, contradicts his testimony at Vienna. He bluntly states that the former testimony was a lie.
- Incurable Cough of Death: At the trial, Boris Shcherbina excuses himself from the courtroom during a coughing fit. Afterwards, his handkerchief is bloodstained, confirming that he has a terminal illness related to radiation exposure from the exclusion zone. Valery is also shown coughing blood while working on his memoirs.
- Instant Cooldown: Actually inverted. The counter-intuitive control rod design meant that inserting them would mean an instant heat up, followed by the normal cooldown. Turns out, when a reactor that's already having a runaway reaction is exposed to the graphite tips of the control rods, the short amount of accelerated reaction time is all it takes for the point of no return to happen.
- Inverse Law of Fertility: In the "Where Are They Now?" Epilogue, Lyudmilla is told that she will never be able to have a child, but this turns out to be wrong (as is Truth in Television).
- Irony: As Shcherbina lampshades at the start of his testimony:Shcherbina: It began with, of all things, a safety test.
- It Will Never Catch On: A positive version at the end of the trial. Charkov vows that the truth of Chernobyl will be covered up and Legasov will die forgotten by history, with all his accomplishments attributed to others instead. Legasov's recorded memoirs and suicide exposed the whole mess to the world, making it impossible for the KGB to continue the facade.
- It Won't Turn Off: The reactor won't turn off even when the shutdown button is pressed—in fact, the faulty control rod design exacerbates the problem from bad but manageable to a true disaster.
- Just Before the End: The episode opens with a normal day in Pripyat, just twelve hours before the explosion. We see many of the plant workers with their families. Vasily plays with their neighbor's baby. Lyudmilla smiles, knowing that one day that will be them. The sequence is capped off by Dyatlov just strolling by on his way to work.
- Just Following Orders: Legasov says at the trial that many people were following orders, himself included, of the Central Committee and the KGB to hide the flaw in the RBMK design.
- Kangaroo Court: Legasov outright says that Dyatlov, Fomin and Bryukhanov will only get a show trial in a conversation he has with Khomyuk. In a rarity for this trope, the trio actually are guilty of everything they're being accused of, with the trial being corrupt in the sense that it's designed to portray the disaster as purely the result of their incompetence, rather than just the end result of a dangerously flawed reactor design on top of a culture that values loyalty, ideology, and secrecy over anything else.
- Last Day of Normalcy: The episode begins in Pripyat ten hours before the explosion. People, some of whom will die as a result of the disaster, are shown going about their lives, the mood is optimistic, the colors are bright (contrasting the muted tones the show has been using) and the soundtrack is upbeat. Then Dyatlov appears and goes to meet with Bryukhanov and Fomin about the upcoming safety test, setting in motion the events that will culminate in Reactor 4 exploding.
- Lecture as Exposition: At trial of Dyatlov, Legasov's testimony starts with a quick rundown of the elements creating the precarious balance at work in a nuclear power plant... and how these changed at the time of the disaster. He is preceded by Shcherbina and Khomyuk giving other details that led to disaster and why Fomin and Bryukhanov are also accountable, not just Dyatlov.
- Long Last Look: At the end of the last episode when Legasov is taken away in a car by Charkov, he gets a shot of looking at the courtroom he is leaving and the friends he is being taken away from one last time. Shcherbina and Khomyuk get similar shots of looking after the car he is being driven away in.
- My God, What Have I Done?: Dyatlov has a look of shock when Legasov's testimony confirms that his suspicions were right and there was a fatal flaw in AZ-5.
- Not So Above It All: Charkov reads Legasov's file and notes that, as Communist Party Secretary at the Kurchatov Institute, he limited the promotion of Jewish scientists in order to curry favor with Kremlin officials, showing that he was just as cutthroat as any other Soviet citizen.
- An Offer You Can't Refuse: After praising Legasov for his performance in Vienna, Charkov shows the reward that awaits him if he continues to tout the Party line and keep quiet about the design flaw. He will be recognized as a Hero of the Soviet Union and promoted to director of the Kurchatov Institute.
- Oh, Crap!:
- A series of these moments occurs in the control room leading up to the catastrophe—first when the reactor begins losing power without operator intervention, indicating a stall; then when the power begins unexpectedly rising again; then when pressing the SCRAM button results in explosion.
- Perevozchenko, seconds before the explosion, when he sees the control rod and fuel channel caps jumping up and down on Reactor #4's steel lid (due to the pressure building up inside thanks to the accelerating reaction).
- It's a subtle one, but Dyatlov when Legasov reveals the flawed control rod design that ensured the reactor's explosion.
- Ominous Hair Loss: Experienced by Professor Legasov; by this stage, he already knows that he's been exposed to enough radiation to guarantee cancer within a few years of the disaster, but finding a clump of hair in his hand confirms that he's running out of time.
- Ominous Latin Chanting: Slavic rather than Latin. "Vichnaya Pamyat"—Ukrainian for "Memory Eternal", played during "Where Are They Now?" Epilogue of the episode. After all, a funeral rite just fits a postmortem.
- Pillar of Light: A faint blue sky beam emerges from the nuclear power plant once it explodes. It is ionized air that is the first clear indication that the core is now exposed to the exterior.
- Poor Communication Kills: As Legasov points out, even someone as pig-headed as Dyatlov probably wouldn't have been so reckless if he'd have been told about the crucial design flaw in the reactor control rods. (Indeed, the real Dyatlov was adamant that the reactor's flawed design was what caused the disaster.)
- "Ray of Hope" Ending: The Real-Person Epilogue at the end does a pretty good job of hammering home the devastating consequences of the disaster, and the sacrifices and sufferings of the people involved. However, the epilogue does have a few bright spots that prevent it from becoming a Downer Ending. Firstly Ananenko, Bezpalov and Baranov to the surprise of most people survived the very dangerous mission to open the gate valves. Secondly, Lyudmilla Ignatenko was able to eventually give birth to a son, confounding medical opinion that the radiation exposure had rendered her unable to have children.
- Readings Are Off the Scale: The conditions in Reactor 4 during the safety test create a feedback loop where more and more power is generated with nothing capable of calming it down. The last recorded power output before the reactor blows up is 33,000 megawatts, when it was designed to operate at 3,200 MW.
- Real-Person Epilogue: The very end has this, showing pictures of the real people and places involved while explaining what happened to them.
- "The Reason You Suck" Speech: Legasov does this to the entire Soviet state during his testimony at Dyatlov's trial, stating that the entire reason the Chernobyl explosion happened in the first place was because the workers were not told that the AZ-5 button, which was supposed to serve as a fail-safe during an emergency situation, could actually trigger a disaster; all sixteen of the other existing RBMK reactors have the same design flaw. The Soviet Union lies constantly whenever they're confronted with an unpleasant truth, such as having to admit that the disaster even happened at all, and the only reason that Legasov didn't tell the truth in Vienna was because he was ordered by the authorities to lie.
- Charkov delivers a short, muted, but devastating one to Legasov, listing his affiliations with, membership in, and actions for the Party. Charkov's placcid demeanor holds until he notes that Legasov blocked the promotion of Jewish scientists to curry favour. The flicker of disgust and anger on Charkov's face shows he regards Legasov as an antisemitic hypocrite who is 'merely a dying man who forgot himself.'
- Reclaimed by Nature: During a recess in the trial (which has been ordered held in Chernobyl to illustrate to the rest of the country how safe the town has become) Shcherbina sees a tiny caterpillar crawling across his pant leg and picks it up with his finger, remarking, "it's beautiful." note Even if humans cannot live in Chernobyl for another 24,000 years, wildlife is already adapting to be able to do so.
- Reports of My Death Were Greatly Exaggerated: As discussed in the ending text, the three divers were rumored and believed by the west to have died as a result of their actions, but they in fact all survived.
- Sadistic Choice: The night shift of Reactor 4 can either obey Dyatlov's boneheaded orders to put the reactor into meltdown or get themselves banned from ever working again. They choose the former only because they are unaware of how bad things could get.
- Shame If Something Happened: Dyatlov tells Akimov and Toptunov that if they don't raise the power back up from 30 immediately (against all safety precautions), he will see to it that they never find work in the nuclear industry again.
- Shell-Shock Silence: After the explosion, we get this from Dyatlov's perspective while Akimov shouts his name.
- Smoking Gun: Legasov telling everyone about just how faultily designed the reactor was at the very end of the trial, which reveals things to be more complicated than just the operators' incompetence. Justified because he wasn't supposed to say anything about the subject, and that was the point where he decided he would tell the truth after all, before it was too late.
- Social Climber: Before meeting with Bryukhanov, Fomin merrily tells Dyatlov that once the reactor test is completed, there will be promotions for everyone! Bryukhanov will head to Moscow, Fomin will take his place as chief administrator of the power plant, and someone will have to replace Fomin as Chief Engineer, and it could be Dyatlov or Sitnikov. Fomin squeezes every last drop of enjoyment out of letting Dyatlov know that Fomin holds his future in the palm of his hand, and out of watching Dyatlov swallow his pride and humbly ask to be considered for the position - unaware that he is hardening Dyatlov's resolve that the test must be completed that night, come hell or high water.
- Solemn Ending Theme: The theme that plays during the Real-Person Epilogue, and the credit themes (which often are also scary ending themes).
- Storyboarding the Apocalypse: The episode has Legasov have to give a detailed explanation as to how the explosion happened and the factors leading up to it. Along with his explanation, we're shown what exactly happened in the control room before the explosion and the immediate aftermath shown in Episode 1.
- Sudden Principled Stand: Legasov is interrupted by Dyatlov, and the frustrated judge declares court adjourned, with all given facts seeming to indicate that the problem was solely operator error. Legasov suddenly interrupts the judge, saying he hadn't finished and had more testimony to give, but he is overruled until Shcherbina himself stands up and commands, "Let him finish," which shocks the whole court into silence and allowing Legasov to reveal the true cause of the disaster and call for a refit of the remaining dangerous reactors.
- Suddenly Shouting: Charkov, as he interrogates Legasov at the end."Scientists... and your idiot obsessions with reasons. When the bullet hits your skull, WHAT WILL IT MATTER WHY?"
- The Summation: The episode details the precise personal, political and technical circumstances that allowed the disaster to occur, complete with flashbacks.
- That's an Order!: Dyatlov doesn't actually say it, but his increasingly hostile commands convey this. When he orders Akimov to raise the power, in violation of every safety regulation that they have, Akimov asks him to record his command in the logbook. Dyatlov tosses it away.
- Threat Backfire: During Legasov's testimony, the presiding judge warns him that if he continues with his implications that the Soviet state holds some responsibility for the events of the Chernobyl disaster, he will find himself "on dangerous ground". This might have carried more weight if directed at a man who hadn't spent months working around the irradiated grounds of a destroyed nuclear power plant — the same land near where the trial is being conducted — and who knows full well that thanks to radiation poisoning he will be dead soon whether or not the Soviet authorities decide to execute him for his insubordination:Legasov: I've already trod on dangerous ground. We're on dangerous ground right now.
- Throwing Out the Script: Not with a literal script, but Legasov goes Off the Rails with the testimony he was supposed to give at the trial. It's pointed out that he's contradicting what he said in Austria, and Legasov responds that he had lied then.
- Time Skip: This episode takes place over a year after the explosion.
- Unperson: Charkov makes it clear to Legasov that the whole world saw him in Vienna, so it would be embarrassing to shoot him and erase all records of his existence. Instead, he will keep his job and title, but have no work, no friends, no authority.Charkov: You will remain so immaterial to the world around you that when you finally do die, it will be exceedingly hard to know that you ever lived at all.
- Unwitting Instigator of Doom: A power grid controller in Kiev asks Chernobyl to delay the test in order to satisfy evening demand. Both Fomin and Dyatlov agree that they can simply wait.
- During the same meeting, while they are waiting for Bryukhanov, Fomin remarks to Dyatlov that once the test is successfully completed, Bryukhanov will almost certainly be promoted and transferred to Moscow, and Fomin will almost certainly be promoted to replace him, so Fomin will have to nominate someone to replace himself, and the choice is between Dyatlov and Sitnikov. Dyatlov swallows his pride and asks to be considered, but the audience can see him resolve that the test will be completed that night, no matter what...
- Villain Ball: Charkov made a deal with Legasov and Shcherbina, so that Legasov would maintain the cover up when talking to the rest of the world in Vienna in exchange for the KGB arranging to quietly fix the flaw in the remaining RBMK reactors. Months later they had still done nothing, which eventually resulted in Legasov blowing the lid off their entire cover up. Had the KGB honored the deal and fixed the reactors, even just doing so slowly one at a time under the guise of some other form of maintenance or repairs, Legasov would have had no reason to go public. Charkov's refusal to keep his own bargains, due to his narrow-sighted belief that no one would dare oppose the KGB's orders, ended up causing far greater public humiliation to the Soviet Union than there would have been had he simply done what he promised.
- Villainous BSoD: At the trial, Legasov reveals that the AZ-5 SCRAM system, which is supposed to shut down a nuclear reactor if something goes wrong, had the opposite effect, and Dyatlov gets one of these. The look on his face, as he realizes that he is not just The Scapegoat for someone else's screwup, but instead, really is responsible for the reactor explosion, shows that he finally grasps what his actions led to, and he is dumbstruck for the remainder of the trial.
- Wham Line: "It's cheaper."
- "Where Are They Now?" Epilogue: The series ends with this, along with footage of the real people and events.
- Legasov's tapes were recovered after his suicide and circulated through the Soviet scientific community. Eventually, the flaw in the RBMK reactors was rectified.
- Shcherbina died four years and four months after being sent to Chernobyl.
- After their release from prison, Dyatlov died from radiation-related illness while Fomin was given an administrative job at another nuclear plant.
- Lyudmilla suffered multiple strokes and was told by doctors that she would never have a child. They were wrong. She eventually gave birth to a son and they live in Kiev.
- About 100 miners who took part in the digging operation beneath Reactor #4 never lived past age 40.
- It is believed that of all the people who viewed the fire from the railway bridge in Pripyat, none of them survived.
- More than 300,000 people were displaced by the disaster. They were told it would be temporary.
- The total cost in human lives remains unknown. While it is estimated that thousands of people died, the official Soviet figure, which remains unchanged since 1987, is 31.
- Mikhail Gorbachev presided over the USSR until its dissolution in 1991. He later wrote that "Chernobyl was the main cause for the collapse of the Soviet Union."
- A new containment structure was completed in 2017, which is expected to last 100 years.
- While You Were in Diapers: When Toptunov questions him, Dyatlov retorts that he has been working in nuclear power as long as Toptunov has been alive.
- You Are Better Than You Think You Are: During a recess for the trial Legasov and Shcherbina sit in the abandoned town of Chernobyl and ponder how much good they really managed to do amid the Soviet Union's constant push for secrecy and denial of accountability. When Shcherbina despondently grouses that he never amounted to anything of actual value within the party and is now dying of radiation poisoning with nothing to show for it, Legasov invokes this trope in one of the series' most poignant moments:Shcherbina: I'm an inconsequential man, Valera. That's all I've ever been. I hoped one day that I would matter, but I didn't. I just stood next to people who did.
Legasov: There are other scientists like me. Any one of them could have done what I did. But you... Everything we asked for, everything we needed. Men. Material. Lunar rovers? Who else could have done those things? They heard me, but they listened to you. Of all the ministers and all the deputies, the entire congregation of obedient fools, they mistakenly sent the one good man. For God's sakes, Boris... you were the one who mattered most. - You Have GOT to Be Kidding Me!:
- Akimov and Toptunov try to review the sequence for the rundown test, but find many of the steps are crossed out. They are then told to follow the crossed out instructions. During the trial, Khomyuk compares this to Yuri Gagarin being told nothing of his mission into space until he's on the launchpad, with nothing more than a crudely-annotated instruction manual he's never seen before.
- Many people in the Court Room reacts like this when Legasov informs that the Chernobyl Power Plant used a more unstable cooling system than western power plants because it was cheaper.
- Younger Than They Look: The radiation has done a number on Legasov by 1988; he's only fifty-two when he dies, but looks at least a decade older.
- Your Days Are Numbered: Shcherbina tells Legasov that his doctors expect he only has a year to live. He would actually live three more.
