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Nightmare Fuel: Agents of S.H.I.E.L.D.
Akela Amador's situation. Forced to watch her team die, kept in a cell at the bottom of a mine shaft for four years before being rescued. Only for her "rescuers" to implant a cybernetic eye into her head which they use to send her missions and control her with the threat of a kill-switch in the eye.
People with eye issues should stay far, far away from this episode, particularly the scene involving Akela's surgery. Even with network TV limits, the Eye Scream is horrific.
The poor ex-MI6 agent who was also being controlled by the mysterious villain(s) behind the bionic eyes. His frightened "Oh God!" as Coulson flashes his badge will stick with you for a while.
His own Eye Scream of the kill switch being flipped, his cybernetic eye turning around inside his socket before the Gory Discretion Shot censors the rest.
The Girl In the Flower Dress
When Chan attempts to use his fire powers without the use of his blood platelets, he scorches himself. His reaction upon first discovering this says it all.
The second-to-last scene of the episode is our first glimpse of Agent Coulson as anything but his usual straight, calm, collected demeanor, and it's nothing short of pure fury. It's more than a little jarring, coming from him.
Coulson's scar. Saying he simply got shanked is a vast, vast understatement: it's obvious Loki's scepter tore half his chest apart. In "T.A.H.I.T.I." he confirms his heart was torn in half.
The entire idea of the episode. There's an alien virus that can somehow infect humans and kill them with lightning from the inside. Simmons gets it, which nobody realizes until the Bus is in the air. Simmons has a couple of hours to cure herself of a virus that isn't even terrestrial in origin, or the resulting lightning will destroy the plane and kill everyone on-board.
Blake's order to Coulson and Ward that they jettison their "infected cargo" (Simmons) into the ocean. Becomes a case of Fridge Horror when you realize the practical implications of the instruction: they're either going to have to Mercy Kill her first, or force her out of the cargo hold while she's still aware of what's going on.
The stinger includes an exchange certain to send shivers down the spine of anyone who's seen a certain other Joss Whedon show, and know its implications for Coulson.
Coulson: Did I fall asleep?
Masseuse: Only for a little while.
The episode's namesake: Ward being haunted by memories of the time his truly evil big brother dropped his little brother down a well and forced Ward to watch the kid struggling to tread water.
It gets worse. It's never said which brother is Ward. And the 'evil' brother looks an awful lot like Brett Dalton. Add in that he's a HYDRA agent...
A good majority of the episode. From The Bus losing power and almost crashing, to Tobias stalking and imprisoning/incapacitating each member of the team in near-total darkness using his incorporeal state, nearly the entire episode is a seat-gripper.
A particular standout moment: the lights are mostly out, and the emergency lights are blinking on and off. The camera is focused on May in the foreground; when the light blinks on, she's alone. When it blinks out and on again, the threatening silhouette of a man looms in the background. The next time the light blinks out and back on again, the figure is gone.
Mike Peterson calls his son, who happily tells him that his friend is watching him. When Mike asks Ace to put her on the phone, it turns out to be Raina. His son was being watched by his aunt. We never find out what happened to her.
The way Raina reacts to information about the Clairvoyant. She otherwise seems to be the very image of an emotionless manipulator, yet she begs Po for any information about the Clairvoyant and seems to be overwhelmed with childlike joy when he tells her that the Clairvoyant knows of her and thinks well of what she's done.
The Magical Place
Coulson's pleas of "Please, just let me die!" as a multi-armed robot probes his fully exposed brain during his seventh operation. The fact that he had already been through six operations before that one, and also seeing as how he was begging for them to let him die shows just show how much pain he was really in.
Given the reveal that Coulson himself was the supervisor of Project T.A.H.I.T.I., the potential horror of his begging becomes two fold. Not only was he begging to die because he was in extreme pain and agony, but also because at that point he still remembered what happened to the previous subjects and would rather die than experience the same mental degeneration they suffered.
The pocket-sized cryogenic gadget that can completely freeze a whole pool in a matter of seconds. And it does exactly the same to Donnie in the middle of his University lecture hall. And to top it all off, the larger version of said device that can spontaneously create a small hurricane-sized super storm with hail chunks the size of lunch boxes, and it ends up killing Seth. This episode really drives home how terrifying Super Tech can be when used irresponsibly. Reed Richards might not be so wrong about keeping this stuff locked away.
When Skye goes into the basement of Quinn's manor. It's dark, and appears empty at first, but she soon finds a hyperbaric chamber that contains...Mike Peterson. Quinn and a bodyguard soon arrive, guns in hand, and we soon see that Mike is Not Himself.... And then later Skye gets shot twice by Quinn. She struggles to move and weakly say the word "Help" before finally collapsing into a pool of her own blood.Mike's new leg attaching and extending itself is clearly extremely painful.
The blue humanoid concealed in the tank that is not only revealed to be the source of the GH-325 serum that was injected into Coulson (and later, Skye), but is also horrifically ripped in half and looks to be decomposing. Coulson's thousand yard staresays it all.◊
The fact that even Nick Fury himself has gone off the grid just about the same time as Dr. Streiten.
One of Lorelei's slaves strangles his own wife to death because she was making too much noise. And the newlywed man she'd taken earlier (stranding his pregnant wife in the process) ended up backhanded into his car.
The End of the Beginning
Deathlok nearly choking Agent Blake to death.
Upon the agents finding Thomas Nash, the Clairvoyant taunts them through a computer (in a Machine Monotone, no less), and tells Coulson that Skye will be endangered again in the near future, and he won't be able to save her this time.
Poor Fitz, discovering that a friend and colleague is a Double Agent, and then being hunted down on an airplane where there's no escape. On a related note, seeing May go Terminator-mode against him is equal parts this and awesome.
The Bus can be operated remotely.
Simmons and Triplett are at SHIELD during the events of CA:TWS, though mercifully they aren't at the Triskelion.
Turn, Turn, Turn
That heart-stopping instant where it looks like Triplett is HYDRA, locking himself in a room with Simmons and pulling a knife out.
Victoria Hand rounding up SHIELD agents at The Hub to determine who is HYDRA and who isn't. Fortunately it's because she's trying to stop HYDRA, despite what it seems like the episode has been leading up to.
The Reveal of Ward as a HYDRA operative, calmly shooting the agents guarding Garrett (the Clairvoyant), shortly followed by Victoria Hand.
There was something extremely unsettling about the SHIELD emblem on the closing title card being replaced with the HYDRA emblem.
It's implied that instead of killing Fitz, HYDRA was going to somehow force him to work for them against his will. After Garrett would have him shot in the kneecaps for threatening him.
Coulson learning that he was manipulated into choosing all the other members of Team Coulson by May so that they would be capable of killing him if it turned out that he Came Back Wrong.
Garrett's call of "Hail HYDRA!" and its answering echo from the off-screen firing squad facing down Coulson, May and Fitz.
The smile. After Ward kills the guards and Victoria Hand in cold blood, Garrett looks up at Ward and a smile that can only be described as "hellish" spreads across his face... all the traces of Affably Evil are gone in that devilish shot.
Garrett casually thanks Ward for "the tip-off about the Cellist". It seems that Coulson's reunion with his long-lost Love Interest in the next episode might not be under the happiest circumstances...
Any scene where Ward switches between his HYDRA persona and his SHIELD persona is unbearably creepy.
Him calmly listing everything he did to get the team to trust him: acting like someone Coulson would want to mentor, becoming Skye's SO, saving Simmons's life (also gaining Fitz's gratitude in the process), and seducing May.
Garrett's method for getting Ward back into character? Beating the crap out of him until he believes his performance. It helps that Ward is still half-smiling (though it's more like grimacing) through a mouthful of bloody teeth for much of the beating.
Every scene where Skye is unknowingly feeding HYDRA information through Ward, up to and including his arrival at Providence, since the plan from there is to find out as much as he can, kidnap Skye for her password, and kill the rest of The Team.
The Only Light In the Darkness
Poor Audrey, having a mentally-unhinged stalker with superpowers.
Blackout in general is pretty creepy, what with the way the lights go out when he passes by them and his Unflinching Walk. The description of how his powers "fried his brain" was also pretty unnerving, and the fact that he seems to be in a constant pain and the only relief he can find is in the music of a woman who is threatened by his very presence.
Skye finding Koenig's body and discovering that Ward is a HYDRA infiltrator. Her reaction says it all.
Ward's revelation which from the flashback to his childhood in earlier episodes, might be the only truth he tells Skye in the whole episode that not only did his older brother force him to torture his younger brother, but his parents were even worse. In the flashback we see, Ward's older brother threw the younger sibling into a well and then made Ward watch the little boy desperately tread water and scream for help as he fought to keep from drowning. the above spoiler implies Ward did not try to sneak a rescue, HE was made to throw him in there, possibly to his death How the hell were Ward's parents even worse?
Considering that he considered Garrett, and being stranded in the woods alone for six months, the better option... A lot worse.
May digs up a flash drive containing details on the T.A.H.I.T.I. project and at the end of the episode shows it to Coulson. The drive contains one video. It's Coulson himself, revealed to be the director of the project. He advises Director Fury to terminate the T.A.H.I.T.I. project and threatens resignation over it. What's more, Coulson reveals that there were test subjects for the project, all of whom quickly deteriorated after the treatment, and while memory replacement staved off the meltdown, it did so inconsistently. And now this treatment has been given to both Coulson and (incompletely) Skye.
The device Deathlok uses on Ward, stopping his heart until Skye caved and spilled the drive's encryption. Just the idea of such a thing is bad enough!
When it's revealed how Ward killed Koenig; strangled him with a garrote with enough force to not only lift the latter's body off the floor, but slice into his neck and obliterate his trachea.
Skye floating out of the freefalling Lola after not having enough time to put on her seatbelt. And then the malfunctioning thrusters flip them upside down.
The whole team is facing jail time if they're caught again for their continued affiliation with S.H.I.E.L.D. and refusal to turn themselves in. Not only is it quite undeserved and basically an attempt by Col. Talbot to extract more information they don't possess, but Fridge Horror kicks in at the thought of any of these people (but particularly non-combatants like FitzSimmons and Skye) in jail alongside genuinely dangerous criminals.
When Ward finally snaps at Skye on The Bus, it's genuinely frightening, as we get a glimpse of just how psychotic he truly is.
The Reveal of how far back it goes and, consequently, how long the Centipede project has likely been in the works.
The experience of having the cybernetics in one's body (a large chunk of his torso) shocked by an EMP.
The immediate physical reaction to Raina's makeshift attempt to replicate GH-325 being injected into his cybernetics.
Fitz and Simmons getting jettisoned from the bus into the ocean. This is further amplified by them being conspicuously absent from the next episode previews, while the more obvious survival of the rest of the team is spoiled right then and there.
Coulson and the others in Cuba get ambushed by Kaminsky and other HYDRA agents in the dark.
We finally get more information about Skye's past. The village she was found in was destroyed, the whole population massacred, by a pair of monsters who were trying to kill her as a baby. Those monsters were Skye's parents.
An added dose courtesy of Fridge Horror: We still don't know how Skye's parents came to be those monsters. If there's a genetic component, then there's no guarantee that Skye won't one day become one herself. In other words, how much of the survivors' description was metaphor (they're monsters because they slaughtered a village) or literal (they're from another planet/dimension.)
The Beginning of the End
Garrett punching through a US Marine Corps general, pulling out one of his ribs, and stabbing him with it.
Ward and May's climactic fight is one of the nastiest brawls in the entire MCU so far. It involves multiple uses of power tools. She nails his foot to the floor, several times. Ward may have had it coming, but OW.
Cybertek's "Incentives Program" basically composes of holding loved ones hostage in order to compel individuals to work as handlers of the centipede soldiers. And the construction zone Ward and May fight through makes it clear Cybertek was planning to expand it significantly.
Coulson getting up in the middle of the night, and scrawling the same alien language that drove Garrett insane all over the wall. Somehow, his tranquil demeanor while doing this makes it even creepier. This is especially the case if you realize that the writing is the same as the one found on the chalkboard by Ward in "Eye Spy". Gets worse when you listen to the creepy music played in the epilogue.
When Raina tracks down Skye's father, his hand is dripping with...something. What was he doing before she came in?
Coulson and May confronting Ward as he's being taken into custody by the military. On the surface, this seems like a major victory for Team Coulson complete with a "The Reason You Suck" Speech, however the expression on Ward's face is very unsettling, implying he may escape and seek revenge in the future.
Because Garrett has both the GH-325 and the Centipede serum in his system, he can take quite a lot of punishment before finally going down, but his appearance grows progressively more disturbing with each injury. After being shot several times by Nick Fury, his mouth becomes bloodied. His face then becomes covered in blood after Mike blasts him with a missile, and is made even worse when Mike stomps on him. Finally, after thought to be dead, he goes through a Painful Transformation into a cyborg à la Darth Vader, at which point he is instantly vaporizedby Coulson.