Agents of SHIELD has grown into a fine show. It had trouble during the first half of its first season, but once Captain America released the floodgates, it stepped up to the plate. Which is why you might be forgiven for missing the many, many sub-plots that simply disappeared.


In a show like this, it's always possible that sub-plots that were left hanging can come back months or even years later. So, it's certainly true that some of these stories may not be over yet. But given how long it took the first season of Agents of SHIELD to get up to speed (particularly given the major cinematic event it was waiting on), there was no doubt that we would see some minor characters and stories get dropped. Here are just a few.

Graviton


Perhaps the most disappointing sub-plot to all but disappear from the show, and thus the MCU, is Graviton. Introduced as Dr. Franklin Hall in only the third episode, Graviton was one of the Avengers' most dangerous foes. His abilities allowed him to control gravity, which makes him a bit like Magneto, only with fewer limitations or Holocaust allusions. While Hall fell into a gravitonium experiment presumably dying, the episode ends with a hand reaching out of the amorphous mass, implying he could still escape.

Lest we assume that the creators simply ditched this plot altogether after the earliest episodes (not uncommon for a serial drama), Graviton—or more accurately, the gravitonium mass he's been trapped in—appears at least twice more in the series. In episode 18, "Providence," Hydra raids a secure SHIELD facility, stealing anything of value. John Garrett ("The Clairvoyant") retrieves the gravitonium and returns it to Ian Quinn (more on him later). It's seen yet again in the season finale with Quinn packing it into the back of a van. By my calculation, that's around seven months of Franklin being cooped up inside his shiny blob prison. We can only assume he's going to be pissed when he gets out. If he ever gets out.


Ian Quinn and Cybertek


While we're on the subject, at the end of season 1, Ian Quinn (seen above in a pretty pink dress...I think...) leaves with Raina. As they load up their gravitonium, Raina tells Ward that the element was "given to us," implying she's working with Quinn. However, as early as the end of that same episode, Raina is seen meeting up with a man who is revealed to be Skye's father, sans Quinn. While he's not necessary for that specific meeting, it sets the tone for how Raina and Quinn work together the next season: not at all. Despite being free from SHIELD, allegedly tied to Raina, and possessing at least one item of extraordinary power, Quinn hasn't made an appearance once.

Quinn's absence is particularly noteworthy given his position with Cybertek. While the heavy implication in the season finale is that the destruction of Cybertek's manufacturing facility means the company is done for, that leaves one big question: where, exactly, was Quinn running off with the gravitonium to? Did he plan to keep it in a basement and poke it with a stick until it made millions of dollars? Certainly Cybertek had other facilities or assets. Even with the death of a general on company grounds and SHIELD's attack on a base where weapons are developed for the US government (you know, I can see why Talbot might misinterpret the situation), it's not impossible to imagine Quinn played the victim, convinced the government that it was all Hydra's fault (technically true) and is still out there, up to no good. So far, though, we haven't heard so much as a local news story about his antics.


The Rising Tide


While Skye may have grown into her own in season 2, one of the chief complaints from the initial season was that she felt shoehorned into the team. Introduced as a "hacktivist" for a group called the Rising Tide, she gains the attention of SHIELD by attempting to break into their systems. Which she is apparently able to do from a laptop. In the back of a van. That she lives in.

In the second episode, we see a touching, if baffling scene where after helping her newfound team on a mission, Skye gets an "untraceable" (see above) message from the Rising Tide, claiming they're in a "holding pattern." She replies with the highly adaptable hacker phrase "I'm in," and goes dark. The implication is that she is intentionally trying to gain access to SHIELD for nefarious purposes. We later learn that apparently she only wants information on her parents, but the group she was working for simply evaporates.


This wouldn't be too suspicious if that's where it ended. However, we see an appearance from at least one other member in episode 5, "Girl in the Flower Dress," where Skye's ex-beau Miles Lydon gets Skye in a bit of a pickle over stolen information. Skye's qualifications with the Rising Tide were also what allowed her to gain entry to Ian Quinn's compound in The Asset (the same episode where we met Graviton), so it seems the group was meant to consist of more than just her and Miles. In fact, they've made an impression on the international community. Yet,fter the fifth episode, none of them are heard from again. Given Skye's "true" reason for infiltrating SHIELD, it seems like the showrunners don't care much to return to this rapidly disappearing beachfront plot.

Deathlok


In defense of Mr. Peterson, Deathlok's arc was pretty well wrapped up by the end of season 1. We watched his transformation from a Centipede-infused superhuman to a cybernetically-enhanced mega warrior. His devotion to his son, combined with the knowledge of the terrible things he'd done, made him wracked with guilt and he elected to leave, rather than return to his family (or SHIELD for that matter).

There's no specific reason for Deathlok to return like there was for Ian Quinn. However, in the season finale, Mike says that SHIELD is free to monitor him while he "makes amends for his actions." What kind of amends are you gonna make there, Mike? Because I can think of a pretty good one: helping what's left of SHIELD take down Hydra. Director Coulson's got a big job ahead of him and few resources (a fact that season 2 simply could not shut up about). SHIELD could use a guy like you on the team.


Oh, well. We may not have a superpowered robot man on the team. But check out that new roster. We have Agent Triplett, the grandson of one of the Howling Commandos! He'll be useful for...oh, wait. Okay! Well, what about Lucy Lawless? The gravitas of having Xena on the team surely counts for...oh, okay, one episode. Well, there's Mack! He seems like a cool guy. He'd be helpful in a fight...or, alright, maybe he'll just get possessed by alien demons or whatever.

God damn it, Mike. Get off your ass and start making amends already.

The Original Dollhouse


While we're reaching for connections, it's worth mentioning this little scene in episode 8, The Well. While we know now that the TAHITI project involved using alien biology, combined with radical memory-altering technology to bring an Avenger back to life, one of the first hints we have that something nefarious was going on occurred in the stinger to the eight episode. Coulson has a dream about his recovery in Tahiti. As he receives a massage from an unnamed masseuse, they exchange this line of dialogue:

Coulson: "Did I fall asleep?"

Masseuse: "For a little while."

The observant viewers in the audience may recall that this is precisely the exchange used in Dollhouse when a doll's memory is wiped or changed. A memory wipe, you say? Not unlike the one Coulson underwent. The reference may be a throwaway gag, but the only reason we dismiss it as a joke is because there aren't any superheroes in Dollhouse. Frankly, I miss the conspiracy theories, though. Isn't it just a little bit possible that the Inhumans are actually just early iterations of the dolls in okay fine I'm done.


And The Rest


Every show goes through some changes in the early stages of its life cycle, so it's completely normal that many smaller things would vanish or change. In no particular order, here are a few more changes that we've all completely forgotten about since last year:

The even more miraculous holograms: It's no secret Marvel loves itself some floaty holograms. Despite their introduction as a pretty specifically Stark technology, they show up more often than Apple product placement. The first episode, however, shows a hologram room built into the cargo area of an airplane that not only can display a 3-dimensional recreation of a crime scene, but does so with nothing but corrupted security camera footage. This is all made possible when Skye offers up an audio recording of the scene. One might write it off as a rendering, but the team discovers both Centipede and Extremis technology on the suspect by looking at the recreation. That's some damn magic tech that probably could've been used again later.

It's no secret Marvel loves itself some floaty holograms. Despite their introduction as a pretty specifically Stark technology, they show up more often than Apple product placement. The first episode, however, shows a hologram room built into the cargo area of an airplane that not only can display a 3-dimensional recreation of a crime scene, but does so with nothing but corrupted security camera footage. This is all made possible when Skye offers up an audio recording of the scene. One might write it off as a rendering, but the team discovers both Centipede and Extremis technology on the suspect by looking at the recreation. That's some damn magic tech that probably could've been used again later. The Tesseract-powered 0-8-4: In the second episode of season 1, the team finds an object in Peru that Fitz says is "powered by Tesseract technology." Whether it's an alien weapon or creation of Hydra, it sure seems super useful. While Coulson's team spends most of their time afraid of it, Coulson himself uses it to dispatch Garrett fairly easily at the end of season 1. Yet again, a weapon that might have proved useful when you're on the run from Hydra, the US government, and a shadow alien society.

In the second episode of season 1, the team finds an object in Peru that Fitz says is "powered by Tesseract technology." Whether it's an alien weapon or creation of Hydra, it sure seems super useful. While Coulson's team spends most of their time afraid of it, Coulson himself uses it to dispatch Garrett fairly easily at the end of season 1. Yet again, a weapon that might have proved useful when you're on the run from Hydra, the US government, and a shadow alien society. That one cool Asgardian dude: Does a one-off character


Agents of SHIELD is clearly a much different show than it was before. In the early episodes, we were following fairly generic, cookie-cutter characters as they unraveled the mysteries of Centipede, Cybertek, TAHITI, and various other plot lines that had almost nothing to do with the larger Marvel universe for sixteen episodes while the showrunners carefully danced around the word "Hydra" or the real plot of the show.

Now, everything's changed. We know Hydra still exists, and more importantly, we can explore the rest of the larger Marvel universe. In all the excitement, we may not realize how crazy it is that a basic cable drama is introducing the plot of a blockbuster movie four years in advance. But as we partake of this comic lore-filled feast, let us pause for a moment and give thanks to the plots that came before and gave their lives in service of the greater story.


(Or we'll see them all again in the second half of this season and I'll eat crow. Until then, woo Agent Carter!)