There’s no denying that theMCUcreators and producers are masters at connecting different storylines across the universe. From bringing multiple solo franchises together in theAvengersfilms to growing and developing its ensemble of heroes, there have been many iconic storylines andmoments in the MCU. Across multiple movies and Disney+ series, the MCU has narratively expanded and explored different themes and ideas across other subgenres.
However, there have also been many instances where the MCU has seemingly abandoned what they set up in certain movies of the franchise. From the Hulk’s insecurities about many lost loves, including Betty Ross and Black Widow, the MCU has introduced some storylines that ultimately went nowhere. Yet Phase 4 has recently shown that the franchise can still bring back characters and plot threads long forgotten, like thereturn of Tim Blake Nelson as The LeaderinCaptain America: Brave New World.
It is never too late to bring back a character or plot point. Phase 4 has introduced plenty of storylines audiences are waiting for answers on, like the giant Celestial head inEternalsor what the new Ten Rings organization will be, yet those are new developments. Look back at storylines during the Infinity Saga that the MCU has neglected and deserves a second chance.
Update July 05, 2025: This article has been updated to reflect the recent releases of the MCU, which did address a few of the unresolved plot points and has been updated with more plot lines the franchise has yet to acknowledge.
The Collector’s Collection
Benicio del Toro was perfectly castas Taneleer Tivan, widely known across the galaxies as The Collector. This unique character was introduced to us in the post-credits scene ofThor: Dark World.We learned that Taneeler collects every valuable relic, fauna, or species throughout the universe; from Hela’s helmet to Aether,one of the Infinity Stones. He was nearly able to obtain a second Infinity Stone, but, as time went on, the audience realized that the hype around his mysterious persona was practically made for nothing. As soon as the focus turned to Thanos' quest, The Collector was wiped away. Many assumed he died inAvengers: Infinity Warand it was not revealed untilThe Guardians of the Galaxy Holiday Specialthat he was still alive, and he sold Knowhere to the Guardians.
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An episode ofWhat If…?showed exactly how powerful the Collector could be and with the character a major part ofGuardians of the Galaxy: Mission Breakout Ridein Disney’s California Adventure it feels like there is still more to explore with this character. His collection probably holds even more Marvel easter eggs and cameos that could be fun to explore in future storylines.
Sonny Burch’s Employer
Ant-Man and the Waspintroduced a new villain, the criminal Sonny Birchplayed by Walton Goggins. Throughout the movie, the character is teasing he is after Hank Pym’s Quantum lab for an employer, yet the identity of said employer is never revealed. WithAnt-Man and the Wasp: Quantumaniaheading for a massive multiverse story, this plotline is unlikely to be resolved in that film.
Who is his employer, exactly? It could be used to bring back fan favorite Sam Rockwell as Justin Hammer who has not been seen since the short filmAll Hail the Kingwhich was made canon byShang-Chi and the Legend of the Ten Rings. It could also be The Power Broker, who was introduced inThe Falcon and the Winter Soldier, although that series implied Sharon Carter became the villain in the five years during the Blip which was afterAnt-Man and the Wasp. It could easily be Kingpin, who appeared onHawkeyeand isset to be a major playerin future MCU projects likeEchoandDaredevil: Born Again. There are plenty of characters it could be, and the plotline could be resolved in films likeCaptain America: New World OrderorArmor Wars.
Lady Sif was introduced as a fierce female character inThor, as part of the God of Thunder’s closest circle. She was a respected warrior, always ready to fight side by side with Thor. Once Thor was banished from Asgard by Odin to Earth, she was ready to disobey her new king Loki in order to help her close friend. She also fought in the Second Dark Elf Conflict inThor: Dark World. However, asThor: Ragnarökrolled around and Hela completely took over Asgard, Lady Sif was nowhere in sight.
Of course, the reason for this was scheduling conflicts betweenRagnarökand Alexander’s showBlindspot. Nevertheless, there was no mention or explanation for Lady Sif’s absence.Sif returned inThor: Love and Thunderbut had a minor role. No explanation was given as to why she was not on Asgard when Hela attacked, and what she has been doing in the time since. She was last seen helping train the children of New Asgard in combat following the loss of her arm. Sif feels like a great character underutilized in the MCU and would make for a great recurring character on one of the Disney+ series, particularlyShe-Hulk: Attorney at Law,as she likely would have a fun dynamic with Jennifer Walters.
Mitchell Carson
Mitchell Carson was a spy, acting as a S.H.I.E.L.D. agent, while in reality working for the biggest terrorist organization HYDRA. He’s been an infiltrator ever since the 80s when he tried replicating the Pym articles along with Howard Stark and Peggy Carter. Years later, he was ready to buy the Yellowjacket Suit, so he could supply HYDRA with the Pym Articles. When his attempts failed, once Ant-Man intervened, he managed to grab a suitcase with a sufficient amount of the particles.
Although an alternate ending shows Carson getting captured, the cut didn’t make it into the final version of the movie. Where are Carson and the particles now then? It would be nice to see Mitchell Carson apprehended and taken out earlier in that film, or another project likeIronheartorMs. Marvelseason two while also showing what HYDRA is currently up to in the MCU.
Aldrich Killian’s Advanced Idea Mechanics
Iron Man 3was a controversial film at the time of its release but has grown in esteem since it came out (and is nowcelebrated as a Christmas movie). Many plotlines from that film, including the Mandarin and Ten Rings, have been revisited in future MCU films. However, one major one that hasn’t is Aldrich Killian’s company Advanced Idea Mechanics also known as A.I.M. Killian was one of many villains who come about thanks to the good guys (Tony Stark) messing up and facing little to no consequences for what they did. Stark tricked Killian into thinking he would join his project Extremis (a group of enhanced soldiers), but when he didn’t, Killian went on to create his own company A.I.M., a think tank with sinister intentions.
A.I.M. is a big organization in Marvel Comics, often finding themselves employed by other supervillains to develop technology and also coming into conflict with organizations like S.H.I.E.L.D. and the various Marvel superheroes. A.I.M. feels like a recurring antagonist that would be great for the MCU, one that can pop up across the various Disney+ series and films that connect a wide array of projects and allow a street-level property likeDaredevil: Born Againto tie into something larger scale likeThunderbolts.
The Buyer of Avengers Tower
Spider-Man: Homecomingis one of the most important MCU movies as it established who Spider-Man is in the universe, but it also came with a few status quo shifts. The biggest of which is that Avengers Tower, the headquarters the team had been using for the last few years, was being sold to a mysterious buyer. The team moved to the compound in upstate New York since there was more room, and they were less of a danger to civilians in the heart of the city.
It wasn’t a minor detail either, as the entire third act revolved around moving out of the tower. As Happy Hogan was overseeing transport to the new facility, the Vulture planned to sneak in and rob the Avengers of their most valuable weapons to sell on the black market. It was never revealed in the film who was buying the tower, and it still remains a mystery to this day. As the biggest landmark in NYC, Marvel Studios has gone out of its way to keep the buyer hidden for six years now.
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There have been ample opportunities to reveal who it was in projects likeAvengers: Infinity War, Spider-Man:Far From Home, andHawkeyesince those projects take place in the city, but there’s been nothing.Far From Homeeven has Peter swing past the remodeled tower, but just enough was hidden to keep things a mystery. Whoever the buyer is has been in the city for years now, and yet we still aren’t sure of who they are. Rumors have circulated that the Tower could be converted into the Baxter Building for The Fantastic Four or even purchased by a variant of Kang as it was teased inLokiseason 1. Yet this remains another Marvel mystery that has been unresolved.
Curing Ghost
As the villain ofAnt-Man and The Wasp, Ghost served as an interesting foil for the duo as she could become completely intangible and invisible. Her father was a scientist obsessed with the Quantum Realm and, in an attempt to build a Quantum Tunnel caused an accident that killed him and his wife, while giving Ava her powers. She went on to become an agent of S.H.I.E.L.D. before the organization fell, and she was left completely alone. She began to die as she needed Quantum energy to survive, setting in motion the events of the film where she tried to steal Hank Pym’s lab with the tunnel inside. By the end of the movie, Ghost had been partially healed by the returning Janet Van Dyne, but that wasn’t enough. The post-credit scene established that they were trying to harness more “Quantum healing particles” for their new Ghost friend, but they all ended up getting snapped before that could happen.
Outside of a brief on-screen reference inSecret Invasion, Ghost hasn’t been seen or mentioned since this moment, which took place around seven years ago in MCU continuity. She was completely absent inAnt-Man and The Wasp: Quantumaniaand presumably is still in need of healing particles to survive. The character has beenconfirmed to reappear in 2025’sThunderboltsas a member of that team, so it’s clear that she’s still around, but much has been left to the imagination. Perhaps audiences will finally have questions answered in just a few years.
Thanos' Attack on Xandar
Avengers: Infinity Warfamously opens with Thanos slaughtering half of what’s left of the Asgardian people to get his hands on the Power Stone. When he attacks Thor’s ship, Thanos already has the Power Stone in his gauntlet. Gamora later confirmed that Thanos had attacked Xander “last week” when he decimated the planet, and that’s the last that we’ve heard about the planet. The Xandarians and Nova Corps played a huge role in the firstGuardians of the Galaxyfilm, but since then, they have been an afterthought in the overarching story of the MCU. As the intergalactic police force, the Nova Corps are responsible for keeping order in the Nova Empire. With its population in ruins, it leaves the galaxy vulnerable for attack. Yet since their destruction, there’s been no word on what’s happened to them.
Perhaps the reason why it’s taken so long is that Marvel is waiting fortheir rumored Nova projectto explore this. Richard Rider is a character who was randomly chosen to join the Corps until its destruction, when he would be the last surviving member. Taking on their combined power, he took up the mantle of Nova and fought for his fallen people. That premise is set up very well from Thanos' destruction of the planet and would be the perfect way to answer this question if Marvel ever got around to it.
Doctor Strangeended with Mordo walking away from the heroes, hinting at his fate as Doctor Strange’s arch-enemy. The after-credit scene showed Mordo beginning his villainous plan, to destroy all sorcerers and supposedly was setting the character up as the main villain for aDoctor Strangesequel. That project quickly becameDoctor Strange in the Multiverse of Madness,and Mordo’s role was reduced.
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He is in the movie but not the version audiences met in the previous film; instead, he is a variant from another universe he works with the Illuminati. Doctor Strange does reference how Mordo has tried to kill him in the past, implying the two have had battles off-screen, but it feels like quickly trying to push back a major plot development. The MCU Mordo was initially supposed tobe killed by the Scarlet Witchat the beginning ofDoctor Strange in the Multiverse of Madness, but that scene was deleted, leaving him still active in the MCU. With Doctor Strange currently busy trying to save the multiverse, maybe Mordo can appear as a villain on the upcoming magic-themed Disney+ seriesAgatha: Coven of Chaos.
Replicas of Iron Man Technology
When Tony was called to the court with regard to the dangers of his technology inIron Man 2,a few things were mentioned, Stark is deemed a national threat, but Justin Hammer fails to mention that Hammer Industries has been trying to replicate some of Iron Man’s technology itself. Of course, the attempts didn’t end there. It was revealed that countries like North Korea and China were working hard to replicate Stark’s mechanisms. Tony assured everyone that it would take them at least ten years to even scratch the surface of his works. Well, more than ten years have passed since, but there’s suddenly no word from those countries. What happened to their hard work to imitate the Iron Man technologies?
The question of Tony Stark’s technologyis one that Marvel is set to address with the upcoming filmArmor Wars. The movie will focus on War Machine dealing with the repercussions of Tony Stark’s technology getting out into the world. This was first teased in the end credit scene ofThe Falcon and the Winter Soldierwhen Sharon Carter aka The Power Broker revealed they had access to government resources and weapons which include Stark Tech drones for Damage Control that were confiscated inSpider-Man: No Way Home. Other projects like Secret Invasion and Thunderbolts will also likely play a role in setting this up, and Marvel might use this to introduce other armored-themed villains from the comics like Titanium Man, Crimson Dynamo, and Ezekiel Stane.
Spider-Man: Homecoming’safter-credit scene teased the introduction of another Spider-Man villain,Mac Gargan aka The Scorpionplayed byBetter Call Saulstar Michael Mando. Gargan appeared earlier in the film as a criminal Spider-Man stopped, and Vulture and his team were working on “The Gargan tail,” clearly setting up his eventual transformation into Scorpion.Spider-Man: Homecomingsaw Gargan approach Vulture in prison, wanting to get revenge on Spider-Man and proposing a team-up.
Yet the Spider-ManMCU franchise moved on, and Scorpion was quickly forgotten about.Spider-Man: Far FromHome featured an international setting with Mysterio as the primary villain, andSpider-Man: No Way Homewas a multiversal team-up featuring a variety of Spider-Man villains from past film iterations. Scorpion was teased as the next villain, and the movies never delivered on him, but everyone assumes it is a sure thing based on the character’s popularity and the last film’s box office performance. The next Spider-Man movie will likely be a smaller-scale film, and that might be the perfect time to bring back a street criminal like Scorpion.
The Kree certainly picked a lot of fights in the cosmos. The MCU established their empire as having been at war and almostdestroying the Skrulls, while also engaging in a generation-spanning war with the Xandarians and the Nova Corp. The Kree were an alien empire fighting on multiple fronts.Captain Marvelended with Carol Danvers telling Yon-Rogg she was going to end the Kree Empire and the war, which audiences briefly saw inThe Marvels. This is used to explain why Carol Danvers did not return to Earth, as she was left dealing with a galaxy that had been destabilized, while also explaining Ronin’s Kree faction inGuardians of the Galaxy.
Yet there feels like a lot of this story left to explore, as much of it was rushed over inThe Marvels. In many ways there is a whole Captain Marvel sequel here to explore, showing the fallout of Carol’s actions on the galaxy. Marvel has also not really gotten into explaining the various levels of Kree government how they were able to get away with slaughtering the Skrulls and why other alien empires knew they were at war with the more respectable Nova Corp. While much of this is in the MCU’s past, there are plenty of stories to explore concerning Marvel’s cosmic history.
