Agents of S.H.I.E.L.D., ABC, Tuesdays 10pm
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Caution: So many spoilers!
Season 4a: Ghost Rider (episodes 1-8)
As the flash-forward at the end of last season showed, Daisy is now a renegade vigilante (whom the media have dubbed "Quake"), and is considered a criminal. But what she's really doing is fighting against the Watchdogs, who are still trying to eliminate all Inhumans. Meanwhile, another vigilante, Ghost Rider, is taking out various bad guys, himself. I should say, Ghost Rider is a character I've never read any comics about, but I've long been vaguely aware of him. There have also been some movies about him, but I haven't seen them (though I did try). Anyway, there have been several incarnations of the character, I guess, but the one in this season of SHIELD is Robbie Reyes. Over the course of this story arc, we get to know Robbie better, and learn how he became Ghost Rider, and what all that entails. (Basically, he made a deal with the Devil, which involved gaining certain supernatural powers, hunting down bad guys, and killing them. Though actually it's not Robbie himself who has the powers; Ghost Rider is a demonic being that takes over his body, periodically, and transforms him. Robbie seems to have some control over when this happens, but perhaps less control of what Ghost Rider does while he's transformed.) It's not long before Daisy crosses paths with Robbie, and they begin sort of working together (though it takes awhile for them to trust each other). She also meets his paraplegic younger brother, Gabe, who has no idea that Robbie is Ghost Rider.
Another thing we learned in last season's flash-forward is that Phil Coulson is no longer the director of SHIELD. This season we learn that that position now belongs to Jeffrey Mace, who I guess is popular with the public because of a heroic act to save others during a bombing in Vienna. (At first I thought it was said he was a soldier, but later I became unsure what his job was, prior to becoming SHIELD's director.) He seems like a pretty friendly guy, for the most part, but there's still a certain amount of distrust between him and Coulson's team. And yet another thing we saw last season is that Dr. Radcliffe had created an android named Aida, a fact which this season he has to keep secret from his new allies in SHIELD. However, Fitz soon discovers his secret, and has to hide it from his friends, including Simmons. Keeping this secret is difficult for Fitz, especially with regard to Simmons. However, it's necessary, because Mace requires her (as one of his inner circle) to regularly take lie detector tests.
The main storyline in this arc involves a powerful, apparently magic book, called the Darkhold. Robbie's uncle, Eli Morrow, is currently in prison. But at one point, he had been working with scientists Lucy and Joe Bauer, on creating a machine that could utilize the power of the Darkhold. But the experiment went awry, and caused an explosion that turned Lucy and some other scientists into what appeared to be "ghosts," though their current nature is actually more complicated than that. Anyway, they now want to retrieve the Darkhold and use it to get back to normal. (Its location is only known to Joe, whom Lucy has to wake from a coma to learn.) But the ghosts wreak a lot of havoc in their efforts, including making people they touch go crazy. SHIELD gets involved in trying to find and stop them, and eventually this leads to Coulson's team crossing paths with Robbie and Daisy, who begin reluctantly working with Daisy's former colleagues.
While all this is going on, there's a senator named Ellen Nadeer (Parminder Nagra) who is very anti-Inhuman, and is secretly working with the Watchdogs. So there's friction between her and SHIELD, of course. And... we learn that Mace himself is Inhuman (he has super strength), a fact that he eventually reveals to the public. (I thought this would work against him, but somehow it made him more popular than ever.) At one point, Mace sends Simmons on a secret assignment to help a team that has been monitoring someone who's been in a terrigenesis cocoon for seven months. Her efforts help him begin to break free of the cocoon, but before she can learn anything about him, she's taken away again, and returned to SHIELD. It's eventually revealed that Eli was responsible for the explosion that turned Lucy and the others into ghosts, as he wanted to take the Darkhold's power for himself. Now, he escapes from prison, and finally gets his chance to obtain that power. He gains the ability to seemingly create matter from nothing. However, unbeknownst to him, he's merely taking matter from another dimension. And in their efforts to stop him, Coulson, Fitz, and Robbie become temporarily trapped between dimensions (in an episode that reminded me a lot of the "Star Trek: The Next Generation" episode The Next Phase). They're eventually brought back to this dimension by a portal created by Aida, after she reads the Darkhold. But while Robbie is between dimensions, Ghost Rider temporarily possesses Mack; it later returns to Robbie. In the end, Eli is dragged to another dimension, himself. (And I guess Ghost Rider went with him, leaving Robbie free of it, finally.) Subsequently, we see that Aida is secretly using knowledge obtained from the Darkhold to design an artificial brain. Later, Mace decides to let Radcliffe continue his work rather than dismantling Aida, and sends a SHIELD agent named Nathanson (who'd been seen in a minor capacity in a few earlier episodes this season) to retrieve Radcliffe's research concerning the android. However, Nathanson discovers that an unconscious Agent May has been abducted by Aida, who kills Nathanson to keep her secret. But we also see Agent May back at SHIELD, having a drink with Coulson. Oh, also, Mace redeems Daisy in the public eye, so she gives up her vigilante ways and returns to SHIELD. And... by the end of the arc, Coulson and his team have learned to trust Mace.
During the midseason break, there was a webseries called Slingshot.
Season 4b: LMD (episodes 9-15)
This story arc's subtitle "LMD" stands for "Life Model Decoy," which are essentially androids like Aida, except without artificial intelligence, like Aida has (or is). LMDs have appeared in Marvel comics for decades, though I think I first heard of them probably during season two of this show, when there was some fan speculation online that the Koenig brothers might actually be LMDs. Well, nothing ever came of that, but now they're finally being officially introduced. (I don't recall whether Aida's body was referred to as an LMD in the first story arc of season 4, or whether that didn't happen until this arc.) Anyway, it's clear that the May we saw with Coulson at the end of the previous arc is an LMD created by Aida, for purposes as yet unknown. But when Radcliffe and Fitz are ordered to wipe Aida's memory of the Darkhold, she fights back, having given herself "upgrades," apparently including human emotions. So she's afraid of dying, which a memory wipe would be equivalent to. So she takes over the SHIELD base and tries to escape with the Darkhold, but is ultimately beheaded by Mack. (Throughout the episode, he and Yo-Yo had some very fun banter about movies featuring robots turning against humans.) However, we later learn that Aida hadn't become sentient after all; it was all just a ploy by Radcliffe, who wanted to obtain the Darkhold for himself. And Aida's AI is already in a new LMD. And May's LMD is still at SHIELD, though apparently even fake May doesn't realize she herself isn't the real May.
Meanwhile, we learn that the Inhuman in the terrigenesis cocoon Simmons had helped with is Vijay Nadeer, who is Senator Nadeer's brother. (I mean, if that was revealed last season, I don't remember it.) Now that he's out of the cocoon, she wants her Watchdog allies to kill him. She loves him, but apparently they had both previously promised each other that if either one ever became Inhuman, the other would kill them. At the end of the first episode of the arc, the senator ends up killing him herself, and has the Watchdogs dump his body in the ocean. However, the body then encases itself in a new cocoon, so Vijay may not be dead, after all. Also, Coulson and Mack discover that Director Mace isn't really Inhuman, he's just been receiving regular injections of a modified version of Calvin Zabo's serum, which the government had secretly developed in Project Patriot. Coulson decides to keep Mace's secret and let him remain as the public face of SHIELD, but from then on, Coulson goes back to calling the shots.
Eventually, LMD May realizes she's not the real May, but her programming won't allow her to tell anyone. But SHIELD finally learns that Radcliffe was behind Aida's actions, and arrest him, only to discover the Radcliffe they had was another LMD. The real Radcliffe and Aida are still elsewhere, keeping the real May sedated, with her mind hooked up to a virtual reality world called "The Framework." And they're working with Nadeer, who sends them to someone called "the Superior," who is the new head of the Watchdogs, I guess. He's actually an industrialist (and major badass) named Anton Ivanov, who has an old grudge against Coulson. They learn that Coulson had entrusted the Darkhold to Billy Koenig, so they try to obtain it from him, in an amusing episode that also includes Sam, and two previously unseen Koenig siblings, another brother named Thurston, and a sister called L.T. (And the whole idea of the Koenigs being LMDs is finally, conclusively put to rest.)
Ivanov sends a Watchdog named Tucker Shockley to expose Senator Nadeer to terrigen, to find out whether she's a potential Inhuman like her brother was. Instead, it turns out Shockley was a potential, and he gains the power to... well, explode. And then reassemble himself. The first time he explodes, he kills Nadeer. Later, Fitz and Simmons create a containment unit in which to capture Shockley. But Ivanov and his men capture Mace, and begin torturing him. SHIELD eventually show up at Ivanov's base to rescue Mace, and after an amusing confrontation between Coulson and Ivanov, Daisy cripples Ivanov. But later, Aida creates an LMD of Ivanov, which will be controlled remotely by his brain, which Aida had preserved. Meanwhile, Fitz and Simmons discover that four of their teammates (apparently Coulson, Mack, Mace, and Daisy) had been replaced by LMDs before returning from the rescue mission. But it later turns out that Fitz was an LMD, and Daisy wasn't. (Though there's a whole army of Daisy LMDs waiting to be activated.) Daisy overpowers the other LMDs, while Simmons recruits various unnamed lower level SHIELD agents to escape from the base. The May LMD sacrifices herself to let them escape and blow up the base after the real SHIELD agents have flown off in the Zephyr. From there, Simmons and Daisy hack into the Framework, to locate the consciousnesses of their friends, and try to wake them up. That effort will be the focus of the third arc of the season....
Season 4c.: Agents of Hydra (episodes 16-?)
Details coming soon-ish.