Phase 2 of the MCU saw Marvel Studios scale new heights and break new records with six new, successful movies – but elsewhere, the MCU grew like never before with the addition of a handful of TV shows set in the same universe, starring supporting characters and villains from the movies, on top of expanding the universe’s mythology by introducing elements the movies have barely touched on so far.

There’s been three new Marvel shows thus far, but the longest-running of them all is Agents of SHIELD, Marvel Studios’ first television effort that has been running for two seasons and 44 episodes currently. SHIELD initially attracted a great deal of criticism for feeling tangential to the movies despite the presence of Phil Coulson (Clark Gregg) as the lead character – but, as the show has progressed, it’s becoming a great deal more integrated into the wider universe, particularly in season two.

Starting with the obvious ways in which SHIELD has tied into the MCU movies – the crossovers with three Phase Two movies:

Thor: The Dark World

Agents of SHIELD was still very much in its infancy when Thor: The Dark World hit cinemas back in November 2013, so it’s probably not a surprise that the show’s crossover with The Dark World wasn’t exactly the most accomplished.

It’s also by far the smallest direct tie-in the show has had with a movie – the impacts of future movies would be felt over multiple episodes, whereas The Dark World‘s crossover is confined to just one episode; episode eight of season one, titled The Well. It’s probably generous to even say that the crossover was confined to one episode – despite heavy promotion beforehand, the only real tie-in with the movie is a brief three-minute scene at the top of the episode depicting the main characters cleaning up some of the debris left by the final battle between Thor and Malekith, with a few slightly gratuitous references chucked in for good measure.

The rest of the episode is generally divorced from the events of that movie – it’s still connected to Norse mythology, and a central character is an Asgardian, but the main story of the episode doesn’t reference or connect to any of the events of The Dark World. Therefore it’s safe to say that the The Dark World crossover was brief at best – something of a prototype for further, more in-depth crossovers with the movies. The Well expands the MCU’s Asgardian mythology a little by introducing a weapon known as the Berserker Staff, but the show’s later crossovers with the Thor world in seasons one and two are actually far larger in scale, and tie into the movies in a more meaningful way than the mostly throwaway crossover with The Dark World, which only really ties into the movie in a checklist-style manner before moving onto its own story.

Luckily, SHIELD‘s next direct crossover with a movie fared a little better…

Captain America: The Winter Soldier

Part of the problem with the initial Thor crossover was that, at this point, the world of Thor was mostly divorced from the slightly more grounded feel of SHIELD and its characters – with The Dark World having no major impact on the MCU as a whole beside Thor’s inner circle, all SHIELD could really do was show the clean-up, and not much else.

However, things were a little different with The Winter Soldier. The MCU has been compared to an anthology TV show before – and sticking to that idea, it’s safe to say that Captain America’s second outing was a mythology episode of sorts, with the events that transpired in the movie changing the landscape of the universe as a whole. Most notably, it’s the reveal that SHIELD was infiltrated by HYDRA at the outset, and its subsequent destruction that had particularly large ramifications on the wider MCU.

Unsurprisingly, Agents of SHIELD was pretty much turned upside down by these events, with the final six episodes of season one functioning as an extended tie-in with The Winter Soldier. The crossover, which began in arguably the first truly great episode of the series, Turn, Turn, Turn, was a far more accomplished and well-executed one than The Dark World‘s tie-in, for quite a few reasons.

With only an hour or so in which to explore the huge revelation about SHIELD, The Winter Soldier was understandably far more concerned with the bigger picture, such as the 20-odd million people in danger from HYDRA’s Project Insight. It showed the fall of SHIELD through a zoomed-out lens, focusing on the major impacts on the world as a whole, and how the revelation affected some of the MCU’s biggest characters such as Captain America. On the other hand, Agents of SHIELD, with a hell of a lot more time on its hands, was able to take a more personal and intimate approach to exploring the fall of SHIELD, choosing to focus on the impacts the revelations had on some of the regular employees such as Coulson and his team, and the major upheavals that HYDRA’s emergence brought about (thanks, Ward!) within that relatively small circle. It’s a more character-based approach that exploited the advantages of serialised, long-form television – it’s no wonder, really, the Winter Soldier tie-in is seen as a turning point for SHIELD in terms of quality by many.

Avengers: Age of Ultron

Agents of SHIELD was in the final stages of season two when Age of Ultron rolled around, so it wasn’t a real surprise that the tie-in with the second Avengers wasn’t quite as ambitious as the Winter Soldier tie-in. Elements of Age of Ultron crept into three episodes towards the back end of season two, such as the brief presence of movie character Dr List (Henry Goodman), and a sudden resurgence of HYDRA, who had pretty much faded into the periphery at this point.

The major plot point that tied into Age of Ultron was the Theta Protocol – mysteriously introduced as a secret, ambitious project of Coulson’s well before Age of Ultron hit theatres, Theta Protocol was a source of conflict and intrigue on the show for a few episodes before the post-Ultron reveal that the Protocol was in fact the helicarrier used by Nick Fury and co. to rescue civilians during the Battle of Sovokia in the third act of Age of Ultron. The Theta Protocol was actually pretty important to fuelling Gonzales’ paranoia about Coulson’s secret-keeping, and facilitating the brief betrayal of Agent May – so, even if the plot point was mainly in service of Age of Ultron, it had a reasonably important impact on the ongoing plots of SHIELD; a far cry from that extraneous and vaguely embarassing attempt to tie-into Thor for about three minutes.

It wasn’t just the Theta Protocol, however – the ongoing storyline went a little off-piste for an episode that reunited the original team (or the Dirty Half Dozen, if you want to go for that) for a so-called rescue mission. The emphasis is on ‘so-called’, with the subsequent reveal that the true purpose of the mission was to retrieve some reasonably important data. How important? It’s the data that allowed Maria Hill (Cobie Smulders, in a brief cameo) and the Avengers to track down Loki’s sceptre in Baron Von Strucker’s Sokovian fortress, making Coulson indirectly responsible for the creation of Ultron and the loss of thousands of lives. Oops.

The common theme here is leading in rather than following on – though SHIELD briefly depicted the aftermath of Ultron in a news broadcast, the major tie-ins here were done and dusted before Ultron hit theatres. It’s debatable as to whether SHIELD should have taken such a detour at a late point in the season, but it’s a neat inversion of the usual crossovers that deal with the fallout of the movies, and ensures that while none of the Avengers have any clue about Coulson’s survival, the SHIELD agent/director is still pulling strings and helping the team behind the scenes.

Smaller Crossovers

Asides from the three direct movie tie-ins, there’s also been a handful of crossovers and tie-ins in between movie releases. Season one, for instance, brought in agents Blake and Sitwell from the Marvel One Shots and movies for a few episodes, allowing a little more characterisation to be afforded to these relatively minor characters – Sitwell, in particular, is a pretty intriguing presence in retrospect considering his betrayal and death in The Winter Soldier. SHIELD even packed in a brief mention towards Sitwell’s assignment on the Lemurian Star, the boat on which The Winter Soldier begins, counting as a minor yet subtly important tie-in with The Winter Soldier. Considering that episode also aired before The Winter Soldier, it’s also the first proper attempt at a lead-in into a movie.

Likewise, Maria Hill has also put in a couple of appearances towards the end of seasons one and two. Her role in season one may have been a little more substantial – helping Coulson in the battle against Garrett and Ward while SHIELD crumbled, but her brief cameo in season two was a far more direct crossover with a movie, with Hill serving as a liason of sorts between Coulson’s SHIELD and the Avengers in the Age of Ultron tie-in episode. In a set-up of sorts for the then-upcoming Agent Carter, Peggy Carter popped up briefly a couple of times for flashback scenes with villain Daniel Whitehall (Reed Diamond) – in fact, the very first scene of season two featured Peggy Carter and a couple of the Howling Commandos, in a scene that set-up the entire arc of season two with the introduction of the Obelisk. Admittedly, Peggy could have been replaced with another agent with little difficulty, but her scenes did a great deal to flesh out the backstory of Whitehall and show the origins of a couple of plot points shown later in the modern day, helping Agent Carter in her path towards becoming one of the MCU’s most ubiquitous faces.

Asides from the numerous agents of SHIELD that have logged appearances in SHIELD after a movie appearance, Lady Sif (Jaimie Alexander) has also appeared twice, playing a fairly substantial part in both episodes she’s appeared in. Sif’s first episode roughly coincided with The Dark World‘s DVD/Blu-ray release – and, taking place far later on in the season than the initial crossover, it was a far more successful attempt at incorporating elements of the Thor mythos into SHIELD, even packing in a comics villain in the form of minor villain Lorelei, and an intriguing hint regarding ‘Odin’ (at this point, Loki in disguise) wanting Lorelei captured alive rather than dead. Sif’s second, more recent appearance in season two served as a crash course in Inhuman mythology for viewers, sketching in the basics of their Kree-based origins – it’s probably best to leave the Inhumans til later, as the Inhumans arc in season two served more as set-up for Phase Three.

Speaking of the Kree, the blue aliens, seen extensively in Guardians of the Galaxy, played a pivotal role in both seasons of SHIELD as part of the TAHITI arc – first glimpsed in season one, well before Guardians introduced the alien race to the movies, it was eventually revealed in a vaguely off-hand manner that Kree blood was used in the formula that revived Coulson and later Skye. That arc’s mostly been wrapped up, but it’s undoubtedly curious that the show’s two most important figures are running around with Kree blood in their veins – something that could definitely come into play if the show continues to head down the Inhumans route.

How SHIELD Has Hinted Towards Phase 3

As Agents of SHIELD has become more confident in its storytelling, the show has gradually shifted away from its initial role as a minor piece of brand extension that could only react to the events of the movies. The best-known example of this more proactive role in shaping the MCU’s mythology is the Inhumans arc – the seeds were planted for this from the pilot, but it was only the mid-season finale of season two where SHIELD finally played its trump card by revealing that the Obelisk, a recurring MacGuffin throughout the first part of season two, contained Terrigen crystals. Oh, and that Skye (Chloe Bennet) and Raina (Ruth Negga), in the room when the Obelisk finally opened, were Inhumans themselves, who both transformed as a result of the Terrigen mist the crystals released.

From then on, with a central character now revealed as Inhuman and an adaptation of comics character Daisy Johnson aka Quake, SHIELD slowly delved deeper into the Inhuman world, introducing the backstory of the superhumans before revealing a hidden society called Afterlife, led by Skye’s very much not dead mother Jiaying (Dichen Lachman). Jiaying eventually assumed the Big Bad role for the final stretch of season two, accompanied by a gamut of Inhumans that significantly upped the number of powered characters on the show. As of season three, SHIELD has added another Inhuman to the regular cast in the form of Lincoln (Luke Mitchell) – and, going by one of the final scenes of the episode, the accidental release of the Terrigen crystals is going to lead to the introduction of a whole lot more Inhumans in the third season.

The Inhumans movie won’t hit theatres until 2019, so the introduction of the Inhuman mythology five years beforehand is impressively premature, allowing SHIELD to become the very first property to portray the Inhumans in live-action. It’s pretty unlikely that any of the Inhuman characters will actually star in the movie itself, but the Inhuman arc is certainly a far cry from that Dark World ‘tie-in’ in season one, and shows a far greater amount of trust and importance from the higher-ups than was initially afforded in the early days of the show.

A less direct, but still undoubtedly important piece of set-up for Phase Three was found in the Real SHIELD arc in season two. Incorporating elements of The Winter Soldier such as Fury’s notably secretive disposition and ‘greater-good’ attitude, this arc actually bears quite a few parallels to the Civil War story such as a purportedly ‘good’ organisation splitting in two due to a philosophical disagreement on how to handle their operations, with one faction forced to go underground and on the run. Of all the Marvel shows, SHIELD is perhaps the most conveniently placed to heavily set up Civil War in the coming season – and it’s not much of a stretch to imagine that the conflict between Coulson and Gonzales was a prototypal version of the moral disagreements to come.

We already have a possible example of how SHIELD could link into the ‘covert vs official’ battle of Civil War – as hinted at in the season two finale, Coulson and Skye will be assembling a covert team of superpowered individuals called the Secret Warriors in season three. Undoubtedly, this new team won’t stay secret forever – and with several of Gonzales’ ‘Real SHIELD’ followers now working high up at SHIELD, there could be far more fireworks to come within SHIELD if this moderately shady idea is exposed. After all, assembling super-powered people is what Coulson was suspected of doing beforehand – now he’s actually going ahead with the idea, it might not end well…