Nightmare Fuel / The Americans

• In the third episode of season one, Elizabeth coldly kills an innocent security guard who was simply doing his job.
• Those audio recordings and hundreds of pictures of the kids! And this is all done by the KGB to other KGB agents. It really makes you wonder sometimes just how extensively your own life is catalogued and documented.
• Philip and Elizabeth discovering the other sleeper couple and their innocent 14 year old daughter brutally murdered in their hotel room. Also the horrified screams of the surviving teenage son (who had been down at the pool) when he finds their bodies.
• Anton Baklanov's fate - the Israelis hand him over to the Russians for exfiltration. He's so terrified that he begs Phillip to intervene. For added bitter irony, the Russians smooth things over with the Israelis by allowing hundreds of Soviet Jews to emigrate to Israel.
• In "Behind the Red Door", Elizabeth keeps goading Philip to dress up in his "Clark" identity and show her what he's been doing in bed to get Martha to sing his praises. He finally obliges... and it turns out that the secret is horrifically rough sex, which triggers Elizabeth's memories of being raped and causes her to collapse in a crying heap. Afterwards, Philip is so disgusted with himself that he retreats to the bathroom, rips his Clark hairpiece off and looks like he'd very much like to throw it in the toilet.
• Philip infiltrates a college computer lab disguised as a janitor so he can attach a bug to the ARPANET^note a primitive version of the Internet mainframe. He is interrupted and quickly hides when a nameless computer nerd enters the lab to pick up something he'd left behind, but the nerd notices the front panel to the mainframe open and decides to investigate. He finds the bug that Philip attached to the main frame, and suddenly we see Phillip standing right behind the nerd. In the next scene, we see Philip leaving the computer lab pushing a large garbage can with a lid over the top, and it's obvious that Philip killed the nerd and stuffed his body into the garbage can. The whole scene plays out like something out of a movie about a serial killer.
• Being in that sub that sank? Imagine being one of the 160 sailors who presumably had no idea their shakedown cruise was about to be their last cruise.
• In this series, collateral damage is a way of life. On numerous occasions so far — the computer nerd mentioned above, a community patrol officer, a septic tank operator, to name a few — guys simply minding their own business find their lives brought to a sudden and brutal end when they encounter the Jennings — the series' heroes (even Jack Bauer usually avoids killing innocents).
• A particularly disturbing and graphic example of collateral is seen in "Comrades". After dispatching two Afghans in the restaurant Philip rushes away through the kitchen just to find a young kitchen worker cowering under the table. Philip tell's him that "it's OK" and starts to leave. As the poor guy visibly relaxes he is shot through the head by Philip.
• Philip shows up at Paige's church late at night, enraged because the church accepted $600 from Paige as a donation. With how dark and angry Phillip has been feeling lately there really seemed to be a possibility that he was going to kill the pastor.
  • Not to mention the previous scene, where for the first time we see the extent of Philip's anger and how deeply he feels the ramifications of his work for the KGB... the way he shouts at Paige is pretty terrifying.
• In "Echo", Emmet and Leanne's killer is finally revealed... And it was Jared. He murdered his whole family to cover up the fact that he was having an affair with Kate, and his parents didn't want him to become a KGB agent. For added horror, it turns out that that whole sordid affair was the result of a KGB program to indoctrinate the American-born children of the Illegals so that they can create a generation of agents who will be able to infiltrate the US government. And just for one last dose of nightmare fuel, Claudia informs Phillip and Elizabeth that the KGB has its eyes on Paige for their next recruit...
• In the third season premiere, after they have sex in a hotel room, Yousef tells Annelise he wants to run away with her. Annelise then tells him that she's been spying on him, but that she still loves him. Yousef strangles her on their bed. Phillip, who had been listening in in the next room, rushes in too late to stop it. He then tells Yousef he'll help him.
• In the next episode, Elizabeth arrives and she and Phillip place Annelise' naked body in a large suitcase. They have to break her bones in order to fit it in, and they make a horrible crunching sound.
• In the third season premiere, Elizabeth breaks a molar during a fight with FBI agents. It bothers her for a few episodes, but she can't go to a dentist because the FBI is looking for a woman that fits her description. After being tailed for hours and nearly getting captured by Federal agents, she comes home to a relieved Phillip, but she still has the intense pain in her jaw. Without saying a word, Phillip takes her down to their basement and she drinks some alcohol and sits down as Phillip takes a pair of pliers and tries to pull out her damaged tooth. He tugs at it to pull it out and Elizabeth is in agony and trying not to scream. At first, he only manages to extract only a half of it, shaking his head, indicating he has to go in again, much to her horror. The second time, as Elizabeth hugs his neck, he struggles to get out the remaining piece of tooth out. There are closeups of both Phillip's and Elizabeth's eyes, the latter filled with tears. He finally pulls the damaged tooth out.
• Elizabeth killing an innocent factory employee in his garage by kicking the car jack off from his car while he was working under it working and crushing him. All so that his position can now be available to the woman Elizabeth has befriended while undercover.
  • Elizabeth later has to kill this woman as well, to prevent her from going to the police.
• "Necklacing", the South African form of execution where a rubber tire is placed around a person's chest filled with gasoline and set on fire, is shown in all its horror when a vengeful revolutionary uses it on an Afrikaaner agent he captured with the help of Phillip and Elizabeth.
• Anti-apartheid revolutionary agent Hans tries to kill Todd, the South African agent spared by Phillip and Elizabeth in the previous episode. He shoots him in the eye, but he's still alive. They struggle onto the ground and Hans finally chokes him to death.
• An old woman who had the misfortune of working late at a place where the Jennings were planting a bug in an FBI mail robot is forced by Elizabeth to take an overdose of her heart medication. She dies a slow, painful death.
• Nina's arbitrary conviction and execution, after attempting a decent action for someone else for once (Anton Baklanov), is a nightmarish reminder of the price for treason, as was perceived in the Soviet Union, in comparison to the Western nations.
• The entire germ-warfare subplot in season four pretty much runs on nightmare fuel, as the Centre, in a desperate bid to find something that will help them compete with the US, dabbles in procuring biological agents, despite their own expert warning them that it's a terrible idea. Even after Gabriel nearly dies from exposure to one of the samples, the Centre keeps pushing for more potent diseases, forcing Elizabeth, Phillip, and the increasingly-paranoid William to resort to desperate measures to acquire more samples.
  • It even works this way In-Universe, leading both William and Oleg to have strong moral objections to being a part of it. Oleg even volunteers information to Stan to help the FBI stop it, rather than potentially be responsible for the death of "half the Eastern seaboard".
  William: Lassa fever’s a very undignified way to go. You basically dissolve inside, then squirt yourself out your anus in liquid form. First it’s whooosh, then it’s a trickle.
• The season 4 finale reveals that Irina, Philip's old flame from back in Russia who attempted to flee the KGB after becoming disillusioned with their work, has been captured and arrested. You do not escape the KGB. And as Nina demonstrates, the KGB does not take kindly to traitors or defectors.
• During a mission in Oklahoma City, Phillip and Elizabeth break into a lab at night where all kinds of insects are being bred. A lab technician walks in and discovers them. Even though he's much taller than them, he's clearly frightened of these intruders who act very menacing towards him, asking him questions about the work they're doing. Realizing he has no useful information to give them, Elizabeth, who is in front, pushes him toward Phillip, who is behind, and catches him and breaks his spine, killing him with a sickening crunch sound. They take his body out and put him in the trunk of their car outside to be disposed of later. At the time, this murder was done with a righteous anger because Phillip and Elizabeth believed the American government was sending wheat infested with bugs to the USSR that would destroy their crops, starving millions of their countrymen. Later, they discover the the bugs were used to test a strong strain of wheat they were developing and the intent was not malicious at all, and the person they killed really was an innocent.
• In "Tchaikovsky", Elizabeth's attempts to blackmail an old source go horribly, horribly wrong as the source pushes back and tries to kill her. In the ensuing fight, he ends up with his gun under his chin and elects to blow his brains out, and her face ends up being splattered with his blood.
• Elizabeth murders two Russian defectors in their home and leaves their bloody corpses to be discovered by their seven-year-old son.