"Captain America: The Winter Soldier" flipped the entire MCU on its head and forever changed how superhero movies could be. It focused on the evolution of Steve Rogers and S.H.I.E.L.D.'s policing of terrorism on Earth and dealt with Rogers beginning his breakaway from the obedient soldier known as Captain America; an introspective piece that took a mainstream hero to places his ilk had never been before.

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In "The Winter Soldier," the Russo brothers shifted away from the MCU's campy style of storytelling, and truly raised the stakes in a world where Rogers realized few could be trusted, including "heroes." With that in mind, and the overload of comic book movies in the pipelines, CBR decided to look at 15 reasons why this one is the best of them all... so far.

SPOILER WARNING: Major spoilers ahead for the several films in the Marvel Cinematic Universe (MCU)!

15 ITS DEPTH OF VILLAINY

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"Hail Hydra" was as soft as a whisper but coursed through all corners of the MCU. When Rogers and Black Widow deepened their investigation into the current authenticity of S.H.I.E.L.D., they ran into the villainous Arnim Zola, returning from "Captain America: The First Avenger," but this time existing digitally in a forgotten bunker. There, he revealed how he infiltrated S.H.I.E.L.D. and corrupted it, to the point where HYDRA now bred chaos through global politics, superseding even DC's League of Shadows.

Zola revealed their plan was to scare the world into craving security so much, it would compromise its freedom, allowing HYDRA to then take over as the new order. They had succeeded. During the movie, we saw several S.H.I.E.L.D. agents, including Brock Rumlow, Jasper Sitwell, members of the World Security Council and Senator Stern (from "Iron Man") outed as HYDRA moles. Eventually, as part of their purging of the evil society, Widow released the secrets of both organizations online (which Helmut Zemo would use in "Civil War"). Rogers and company truly realized that to build a new world, the old one needed to be broken down, which saw Nick Fury try to reverse HYDRA's poisoning at any cost.

14 THE RUSSOS' DIRECTION

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CAPTAIN AMERICA: THE WINTER SOLDIER - Zade Rosenthal © 2013 MVLFFLLC. TM & © 2013 Marvel. All Rights Reserved.

Few people expected Anthony and Joe Russo to deliver such a spy-thriller, which transcended not only the quippy-action style of the MCU, but their own resume as well. Prior to this film, the only feature films under their belts were the comedies "Welcome to Collinwood," and "You, Me and Dupree" with Owen Wilson and Matt Dillon in 2006. In the ensuing eight years, they did a few shorts as well, but focused on the comedy scene up through "Arrested Development" and "Community," before taking over from Joe Johnston to deliver this 2014 film. And boy, did they deliver!

No one doubted their talent, as fans know Marvel Studios usually hire smartly, but to see them take such a powerful tone and direction was mind-blowing. Many expected them to replicate Johnston's cheesy, lighthearted take on Cap, but the Russos stunned everyone with a total U-turn. Things felt real, and they packed a sense of gravity into it like no other Marvel film. They showed us a world where everyone, even heroes, could be expendable, and really carved out a superb anti-terrorist film.

13 BLACK WIDOW

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In "Iron Man 2," Black Widow (played by Scarlett Johansson) debuted as one of Nick Fury's prime agents, helping investigate how valuable Tony Stark would be to the Avengers initiative. She ended up helping him defeat Whiplash, but throughout Jon Favreau's second film, she felt shoehorned in. Her performance, and overall role, just built the movie up as a trailer plugging S.H.I.E.L.D. as the Avengers recruiting agency.

Here though, Widow was perfectly fleshed-out and done right! We got a comprehensive insight into her loyalty to Fury, but also how far she was willing to go to question her employers. Her fight sequences were spot on, her interactions and chemistry with everyone felt much more organic, and overall, she felt integral, especially to taking HYDRA down. She didn't feel like a prop at all (which the Russos clearly extended with her in "Civil War"), and while Steve battled the Winter Soldier (his best friend, Bucky), her role took a huge twist as she leaked the info on S.H.I.E.L.D. and HYDRA to the public, outing her past misdemeanors as well. This movie made her a hero, not just a peripheral agent.

12 MULTIPLE VILLAINS

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There's a rule of thumb in comic book movies: don't pack them with several villains. This harms their character development as we struggle to connect with them, as per the "Spider-Man" franchises from Sam Raimi and Marc Webb. The Russos, however, bucked that trend by placing quite a few in the mix, but giving them just enough screen time to show their importance. Alexander Pierce was shown as the HYDRA leading S.H.I.E.L.D. astray, and then we saw Rumlow in his pre-Crossbones era. Earlier on, we also watched Batroc get a badass update in the limelight.

Let's be honest though, the real MVP was the Winter Soldier. He wasn't any kind of plotter or cerebral assassin. He was just a gun and knife-toting muscle, executing orders with aplomb. What made him resonate was the manner in how he did it, proving to be Cap's equal and leagues ahead of the other heroes. The Russos clearly showed here how to effectively make an ensemble film, which no doubt helped them get "Avengers: Infinity War." What's interesting is how they inverted their approach in "Civil War," using just one villain in Zemo to pull everyone's strings.

11 ROMANCE ON THE BACK-BURNER

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This film shelved the romantic arc of Marvel's greatest hero and biggest icon, focusing on overall scope as opposed to personal interest. That's pretty damn bold, as most superhero flicks want their lead to have a love interest, especially given how big a deal they were as a couple in the comics. The Russos did sew seeds for Sharon (Agent 13) and Steve to pursue something later on in "Civil War," but here, it was apparent they didn't want to steer Cap clear of the war ahead.

We're not sure if they found it would be too distracting or if Steve himself wanted to finish the mission of purifying society first of HYDRA, but it does stick in line with his first movie, where affairs of the heart came second. Steve was always about living up to the principle of Cap, and the symbol he represented. The chemistry with Sharon (played by Emily VanCamp) was so good, you felt bad and wanted more of them together, but the directors knew that Steve had to focus on being a paragon of virtue and a beacon of hope, especially if he was to redeem a hunted Bucky.

10 EASTER EGGS & CAMEOS

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Marvel Studios love their easter eggs and cameos, which, if not done right, can be a tad distracting. This film, however, clearly wanted to remain self-contained and focused on a singular objective: paving the shaky road ahead for the MCU. The Russos had a plan and executed it well, while teasing the future subtly. It didn't take a genius to know that after this film, things like "Civil War" would come with the fracture of world security. One such easter egg was Sitwell name-dropping Bruce Banner and Stephen Strange.

They were being monitored by HYDRA, and there, you realized that the MCU was much more sinister, and expansive. The Winter Soldier holding Cap's shield (teasing how Bucky ended up donning the Cap mantle in the comics), being treated to Ed Brubaker (his comics curator), and Steve using his "Secret Avengers" suit, are all further examples of the easter eggs packed into the film. Don't get us wrong, there were quite a few, but the Russos used them to complement the movie and not to act as a crutch holding up pivotal scenes. Things got even better at the end with Baron Von Strucker, Quicksilver and Scarlet Witch emerging.

9 REINVENTING THE SIDEKICK

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The Russos showed that equals, not sidekicks, are needed to combat evil. Theirs wasn't the cheesy formula from "Batman and Robin," but one that really constructed a superhero from an ordinary person, thrown into a baptism of fire to help the main character out. Sam Wilson became the Falcon with such ease, and everything about him, from his loyalty to Steve, to how his training helped him prep for Avenger duty, saw him fit in quite easily.

They gave him proper reasoning and motivation to risk it all on the line, as he too was clearly a patriot who stood by Steve's doctrines, just like in the comics. They also powered him up with tech that really made him a logistical asset to the fight, which again was smartly expanded upon in their follow-up movie. The way they bucked the sidekick didn't just apply to Falcon, though, as they evolved Widow as well from being one of Nick Fury's righthand assets, showing that the directors truly wanted to assemble a team, and not just supporting pieces for their key leads.

8 MAN VS. JET

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If it's one person who isn't a godlike entity or armored hero that you'd expect to take down a jet, it'd be Captain America. Boasting nothing but a motorcycle and his shield, he avoided the Quinjet's gunfire that was trying to subdue him when he was deemed a S.H.I.E.L.D. traitor. What ensued was one of the MCU's most profound battle sequences, and all in the space of a couple minutes. Steve flung his shield and took out the jet's engines before leaping off the bike and onto the Quinjet to finish the job.

He clung to the jet and then proceeded to use his shield to dismantle its other key mechanical aspects, and then jumped off with a signature pose that can best be described as comic cover-worthy. He fought the law and the law didn't win. This really played up the essence of the character as a man triumphing over machine and the overall system, illustrating Steve's bravery and fearlessness in fighting for world freedom. This scene perfectly summed up how superheroes transcend their opposition, planting themselves in the roots of truth, and bracing themselves against their oppressors.

7 CHARACTER EVOLUTION

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Most sequels gloss over the shortcomings of the movies that come before them, but this one cleverly addressed and reinforced them, before quickly moving forward to tie in its predecessor's most poignant notes. The Russos made Steve more self-assured and assertive as a leader, which in all fairness he adopted towards the end of "The Avengers," but what they kept was the human aspect of the kid from Brooklyn. Moreover, this movie stuck with the hopeless romantic in him.

We saw it in bits and pieces with glances he shot at Sharon, but the tears came gushing when he met an old Peggy Carter, his flame from the past (and ironically, Sharon's aunt). This scene showed how a hero's origins and perceived death can shape the world for years to come, as it drove Peggy to help start S.H.I.E.L.D. It also showed us that despite Steve's charm and outer mask, the emotional agony a hero carries endures for years. This was evident in Steve putting on a brave face to comfort Peggy when Alzheimer's was wrecking his best gal. In the end, we all wished he got that dance from "The First Avenger."

6 A NEW LEVEL OF BATTLE

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The Russos didn't just elevate the standard of fight sequences for MCU movies, but for all comic book movies. In fact, it had epic action scenes and choreographed fights, which probably only "John Wick" can rival over the last few years. This film adopted a more MMA style of fighting, while incorporating weapons such as knives and guns into it, rather than alongside it. The results were fluid and relentless sequences that kept you on the edge of your seats.

The highway fight segment with Widow and Steve battling Bucky was one that used almost every action aspect the movie had, from machine guns to bazookas to knives to shields to vibranium arms, and left you absolutely breathless. Steve and Bucky at the end also upped the ante, which should have come as no surprise as the movie's first arc showed the heroes raiding a ship to attain data. There, we saw Widow and Cap cut loose like never before. It foreshadowed what the Russos had planned, especially after UFC legend, Georges St. Pierre, gave Steve a run for his money as Batroc The Leaper to open the film.

5 AN INCORRUPTIBLE HERO

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It's hard to paint a hero as someone whose life is on the line, and whose morality is directly down the middle. Even in the comics, Marvel didn't get this right all the time when it came to Steve rising up against authority. In this movie, though, you could see the battle lines drawn and empathize with where he stood. Usually, heroes do take sides, have skewed perspectives, and are somewhat compromised, especially emotionally, but here, Rogers was a rock.

This emotional bias was seen all over in "Batman v Superman" and "Civil War." Cap, though, displayed a stoic stance and unwavering resolve here because he wasn't about politics, but principle. He cast aside emotions (as seen with his potential romance with Sharon) and bit the hand that fed him in Fury, and then S.H.I.E.L.D. In the end, he showed he had no allegiance (also noticed where he scolded Fury for repurposing HYDRA weapons), except to the nation and its people. Steve reminded us that the mantle, the title and the shield mattered little when it came to doing what was truly right. Some may say he was overly emotional with Bucky, but that's family; and even then, redemption and forgiveness are parts of this virtuous journey.

4 NO VICTORY

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At film's end, it was hard to feel like the heroes won. Their spirit and morale were broken. HYDRA had shown how deep its roots ran, and all secrets (as well as S.H.I.E.L.D's) were out there. Widow was answering to congress on whether or not the age of heroes had come to an abrupt end, and public trust was gone. Fury went underground to try to make up for his transgressions and ignorance, while Steve and Falcon decided to secretly track Bucky.

While this didn't indicate that the Avengers took a hit, you could see how things would resonate, especially as Zola dropped a big hint on the assassination of Stark's parents. This ending just offered a temporary respite to take a deep breath for what was to come next. It peeled away the skin and exposed the Avengers initiative like never before, showing flaws and holes in the foundation it was built on. HYDRA was done but the world was visibly shaken with their security now needing significant beefing up. Whether it was Ultron or the Accords, you could have sensed something ominous, albeit laden with good intentions, was imminent.

3 A LEGIT CIVIL WAR

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This dramatic finale set up a lot of things in the MCU, but the domino effect definitely kickstarted "Civil War" most of all. Some may say that with the world in disarray, "TWS" was the catalyst for Stark's response in "Avengers: Age of Ultron," where he built the villainous artificial intelligence as a global security blanket. That's true, but this movie was the one that already put Steve in a cynical frame of mind, which Stark then kept tugging at, from Ultron to the Accords. This movie broke Steve's ability to trust openly, and he got more streamlined as to whom he trusted.

"TWS" also teased that Bucky may have killed the Starks, proved that Widow and Falcon would always lean toward Steve's POV, showed that Fury probably owed Steve more than he did Stark, and painted Steve as a whistle-blower helping exposing HYDRA. This is all not to mention that the Russos had Cap terminate Project Insight, which used helicarriers and the Triskelion as air-based points of attack. All of these proved to be a mini civil war in itself, magnified later when General Ross decided he'd become the new Nick Fury.

2 A BADASS VILLAIN

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Bucky Barnes was endearing, cocky and all about words as Steve's best friend. When he was found and brainwashed by HYDRA, though, he was all about actions as a global terrorist. His identity was no secret to comic fans, but it certainly blew the minds of non-readers who thought he died in the first film. Here, he was reborn, and simply put, he was a stone-cold killer. From trying to repeatedly kill Fury, to making a mockery of the shield when Steve tried to use it against him, to treating Falcon and Widow like sparring sessions, he brought a big game.

Every weapon the Winter Soldier used, every time he utilized his bionic arm, and every moment he appeared conflicted as to whether or not he did know Steve, it all felt like a big whirlwind of emotions. You wanted him to snap out of it because you couldn't root for an assassin (even if you did dig his moves). In fact, it gave Marvel a rare villain that intimidated with just stares, backed up with his fists. He wasn't a talker, but rather, a blank canvas who followed orders, which made it that much more painful to see every blow between him and Steve.

1 SUBVERTED THE SOURCE MATERIAL

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Ed Brubaker's run on "Captain America" gave us some of the best stories of all time, and when he resurrected Bucky as the Winter Soldier, comic fans lost their minds. Many were skeptical, but Brubaker eventually proved them wrong, making him sympathetic upon redemption, while also crafting him as part of a covert trifecta with Steve and Fury. Brubaker eventually had him replace a dead Steve, and Bucky's stories wielding the shield continued to silence critics.

Now, in terms of comic loyalty, Brubaker had several elements there that weren't in the Russos' movie, such as Bucky being a Soviet assassin, ties to Red Skull, a past with Widow and Wolverine, and a destiny with the Cosmic Cube, which would return his memories. All of those were more or less scrubbed for this film, but his overall essence and murderous philosophies were kept. Bucky was repurposed but used in a similar fashion as a terrorist that Steve needed to subdue, and subsequently save. What was subverted, and what was kept from the lore, were amazingly married to produce a script (by Christopher Markus and Stephen McFeely) that was nothing short of a visual spectacle, and emotional rollercoaster.

Let us know in the comments if you thought The Winter Soldier was the best comic book movie ever. If not, what was?