Over the past 10 years, the Marvel Cinematic Universe has more than lived up to its reputation. An interlocking universe of superhero stories, the MCU has made well-known and not-so-well known comic book characters household names, revitalized and jump-started careers, and even had some groundbreaking moments in diversity and representation. In return, this experiment in sprawling, long-term world-building has garnered billions of fans around the world and scored the box office bank to prove it truly is marvelous.

Each of the 20 MCU movies has made hundreds of millions of dollars at the box office, something that couldn’t happen without some serious repeat business. Avid fans of the franchise see each individual MCU entry multiple times, soaking up every character detail and plot point. Given the way the MCU continues to expand, fans have become adept at catching things that tie each movie to previous installments and clues about what might happen in the future. Not to mention, when a new MCU movie is about to hit theaters, fans often re-watch the titles that came before in order to brush up on their knowledge and make sure they won’t miss a thing when they see the newest release. Despite fans’ devotion to the franchise as a whole, however, all 20 movies that are part of the MCU aren't equally worthy of fans’ time. There are some that are endlessly interesting and entertaining no matter how many times they’re re-watched. And then there are those that were great the first time but offer diminishing returns with repeat viewing. Here is our handy guide to which MCU movie falls into each category.

20 ONCE IS ENOUGH: AVENGERS: INFINITY WAR

infinity war high res

Avengers: Infinity War was Marvel’s most superhero-heavy movie yet. It’s undeniably fun to see characters that had previously occupied their own worlds meet and team up. After all, it did have the Guardians of the Galaxy hanging out with Thor, Doctor Strange and Wong taking on the bad guys with Iron Man and Bruce Banner, Okoye and Black Widow backing up Scarlet Witch. These were the moments that made Infinity War so appealing to long-time fans.

Yet, with so many superheroes, the unusual team-ups didn’t have all that much time to establish their dynamics. Each hero had their moment but for many it really is just a moment. Repeat viewing only sheds light on how thin these mash-ups really are. Fingers crossed for something deeper in Avengers 4.

19 REWATCH: DOCTOR STRANGE

Doctor Strange is not the MCU’s best movie, but it is its most visually stunning. Magic was introduced into the MCU before this movie. Thor’s Asgard, Scarlett Witch’s abilities, and the powers of the various infinity stones all brought the mystical into the science-driven worlds of many MCU characters. However, Doctor Strange was the first movie that really delved into the world of magic, exploring what it was and how one could access it.

The journey of Stephen Strange from arrogant surgeon to Sorcerer Supreme is filled with stunning glimpses into the magic of the universe. The kaleidoscopic images conjured throughout the film are amazing and demand to be seen more than once.

18 ONCE IS ENOUGH: ANT-MAN

ant-man

Ant-Man is an enjoyable enough origin story. Paul Rudd is always a fun actor to spend time with, the film is stacked with a bevy of talented actors bringing their A-games to their roles, and the story is definitely amusing. However, in comparison to many other MCU films, this one is a lightweight diversion.

There’s nothing wrong with that, of course, but there are other comedic options in the MCU (see, for example, Guardians of the Galaxy and Thor: Ragnarok) that reward repeat viewing more. Ant-Man is a trifle — worth taking in once, but no further time commitment is required.

17 REWATCH: CAPTAIN AMERICA: THE FIRST AVENGER

captain america the first avenger

The first Captain America outing has the distinction of being the only MCU movie to date that spends almost its entire run-time in the past — the 1940s during World War II to be exact. As a result, it’s not only Captain America’s origin story, it’s the origin story of the organization that becomes S.H.I.E.L.D.

If that wasn't enough, the movie also shows Rogers’ short-lived but chemistry-laden relationship with Peggy Carter and establishes his bromance with Bucky Barnes, the emotional heart of the rest of the Captain America series. With so much going on, this movie deserves at least one re-watch to catch it all.

16 ONCE IS ENOUGH: SPIDER-MAN: HOMECOMING

Tom Holland in Spider-Man: Homecoming

Spider-Man: Homecoming, the third iteration of the Spider-Man story in recent memory, is a charming movie. Of course, fans were already introduced to Tom Holland’s youthful take on the character in Captain America: Civil War. However, this movie does a good job of differentiating itself with a story about the thrills and drudgery of burgeoning superherodom.

Plus, Michael Keaton turns his superhero past on its head to play the villainous Vulture. The tense conversation between him and Holland after Holland realizes Keaton is his date’s father is a doozy. These things make Homecoming the most successful Spider-Man film in the past decade. At the same time, though, fans have simply spent too much time with the character in the last several years to warrant a second viewing.

15 REWATCH: THOR

The first Thor movie stands out in the pantheon of MCU films for the way it contrasts the glamour of the mythological realm of Asgard with the dusty New Mexico town where Thor lands on Earth. In Asgard, Thor is an arrogant hot-head. In New Mexico, he’s a fish out of water who must learn how to think at least a little before he acts.

As directed by Kenneth Branagh, Thor is a strange mash-up of superhero tropes and coming-of-age film. It tears its hero down and builds him back up as a better person before it’s willing to grant him superhero status. Also, the movie’s our introduction to Loki, one of the most compelling villains in the MCU.

14 ONCE IS ENOUGH: IRON MAN 3

In Iron Man 3, Tony Stark’s past comes back to haunt him. Or at least that’s ultimately what happens. However, when the movie was originally teased, audiences were given the impression that this was the movie where Iron Man’s archenemy, the Mandarin, would finally be introduced.

Those who have seen the movie know there’s a big twist that subverts and re-constructs that expectation. It may have seemed like a clever surprise at the time, but despite Ben Kingsley's fantastic performance, it wasted one of Iron Man’s best villains. Between that and the weird interlude that pairs Stark with a precocious kid and the enigmatic motivations of the super-soldiers that keep coming after him, the movie isn’t worth a second watch,

13 REWATCH: GUARDIANS OF THE GALAXY

Groot creates lights in the MCU's Guardians of the Galaxy

Guardians of the Galaxy was a breath of fresh air when it hit theaters in 2014. The movie, about a rag-tag group of misfits and outcasts who join forces, was the first MCU outing that spent minimal time on Earth. Given its anthropomorphic racoon, talking tree, and multi-colored aliens of all kinds, the movie really shouldn’t have worked. Instead it was buoyant and lively, a fun and funny slice of entertainment that introduced some truly unique characters.

The movie deserves a re-watch for entertainment value alone. However, it also has several truly touching passages, including Groot’s moving sacrifice to save his friends and Rocket’s heartbroken response to his loss.

12 ONCE IS ENOUGH: GUARDIANS OF THE GALAXY, VOL. 2

Guardians of the Galaxy Vol.2

Guardians of the Galaxy, Vol. 2 doesn’t quite live up to the high bar set by its predecessor. That’s not to say it doesn’t have some great moments. Between baby Groot dancing the fight away during the opening sequence, Yondu enthusiastically declaring he’s Mary Poppins, and Kurt Russell’s terrific performance, the movie is certainly worth a viewer’s time. Besides, as audiences discovered in the first Guardians, these characters are fun to spend a couple hours with.

However, with the characters and their dynamic now established, and a less compelling story, Vol. 2 simply doesn’t merit a re-watch. Better to take in the first one again.

11 REWATCH: THOR: RAGNAROK

After an underwhelming second outing, Thor: Ragnarok, the third in the character’s stand-alone series, had a lot riding on it — and, boy, did it deliver. Sure, the story is a bit thin, but it introduced audiences to some amazing characters, including Tessa Thompson’s Valkyrie, Jeff Goldblum’s Grandmaster, and Cate Blanchett’s Hela. They’re all wonderful but Blanchett seems to be having an especially good time chewing the scenery as Thor’s bad big sister.

Add to that the buddy comedy between Thor and Hulk/Bruce Banner, the ever-fascinating dynamic between Thor and little brother Loki, and Chris Hemsworth bringing the funny, and you have an exciting romp of a film worth seeing more than once.

10 ONCE IS ENOUGH: ANT-MAN AND THE WASP

Like the first Ant-Man, this sequel is a trifle. And like the first movie with this character, it’s pleasantly breezy entertainment that viewers won’t regret investing time in once. The film has the distinction of being the first in the MCU to include a female superhero’s name in the title, so it’s too bad that the story doesn’t have a bit more heft.

Instead, it has a ho-hum villain, an underused Michelle Pfeiffer, and a rushed ending. The movie is silly summer fun and the use of shrinking and growing makes the fight sequences a gas, but make no mistake, this is second-tier MCU.

9 REWATCH: CAPTAIN AMERICA: CIVIL WAR

Captain America Civil War poster

Critics and fans alike have observed that with its bloated roster of superhero characters, Captain America: Civil War is really a glorified Avengers movie. That doesn’t make it any less compelling as a Captain America movie though. The film plays the world views of Team Cap off of those of Team Iron Man leading to an epic smack-down between former teammates that alone makes the movie worth a re-watch.

In between all that, the film has more on its mind than many superhero flicks, pondering ideas of loyalty and trust, free will and control. For non-fans who aren't as familiar with the characters the movie won't be as significant, but for MCU devotees, this one paid off years of emotional investment.

8 ONCE IS ENOUGH: AVENGERS: AGE OF ULTRON

Avengers: Age of Ultron has a great concept — one of Tony Stark’s creations goes rogue and decides ridding the world of humanity will help it meet its objective. If only the movie’s execution lived up to its ideas. Age of Ultron was disjointed and its characters' motivations were often weak.

In addition, audiences got a half-baked love story between Bruce Banner and Natasha Romanoff, an underwhelming introduction of the Maximoff twins, Thor going off to take a mystical bath for some reason, and the country-destroying mayhem of the movie’s final battle. The film had some positives — the arrival of Vision, Bruce and Tony bro-ing it up for science — but overall, it’s not a film worth dwelling on more than once.

7 REWATCH: IRON MAN

Robert-Downey-Jr-as-Tony-Stark

As the first MCU film, Iron Man has the distinction of setting the tone for everything that came afterwards. And there may be no better tone-setter than this film. Much of the credit goes to Robert Downey, Jr. whose Tony Stark is a fascinating character no matter what story he finds himself in. In a lesser actor’s hands, the character may have been entertaining, but he wouldn’t have had the manic life Downey consistently brings to the role.

The movie also establishes the MCU’s mix of light and dark. Stark goes through a harrowing ordeal in the movie, but he’s no brooding superhero. The exuberance and joy he experiences while testing his Iron Man suit are infectious — a great pick-me-up worth watching again and again.

6 ONCE IS ENOUGH: THOR: THE DARK WORLD

An image from Thor the Dark World.

Thor: The Dark World, the second of Thor’s stand-alone movies, has the elements of a great film. Ultimately, though, the whole is much less than the sum of its parts. This is especially true because the movie spends so much time establishing its villains, the Dark Elves. However, the Dark Elves are ineffective bad guys — outside of looking menacing and a willingness to kill to get what they want, there’s not much there.

By far the most interesting part of the movie revolves around the dynamic between Thor and Loki. The movie comes alive when the brothers are verbally sparring, making it worth a single viewing. However, with all the other characters and plot points it crams in, there aren’t nearly enough of these scenes.

5 REWATCH: CAPTAIN AMERICA: THE WINTER SOLDIER

Captain America Winter Soldier

Captain America: The Winter Soldier features a heady, absorbing story that speaks to present-day concerns. However, it’s the film’s emotional reveals that pack a wallop. First, Nick Fury is taken out in a spectacular action sequence that leaves many of the characters reeling. Then, fans learn that Cap’s BFF, Bucky is not only still alive but working for the enemy as the Winter Soldier.

Cap’s discovery of the Winter Soldier’s true identity and his desperate attempts to break through to his brain-washed brother-in-arms during their final fight gives these scenes extra emotional weight. It’s gripping entertainment that's well worth multiple viewings.

4 ONCE IS ENOUGH: IRON MAN 2

Iron Man’s second big-screen outing was a big let-down after his triumphant first feature. While the movie had some flashy villains and introduced us to Scarlett Johansson’s always welcome Black Widow, overall the story lacked the sense of wonder and playful zing of the original. Downey was still aces as the spirited superhero, but sometimes his flippant response to his circumstances could shade into obnoxious, both for the other characters and the audience.

Ultimately the film was too busy and the overstuffed plot more complicated than necessary. Iron Man 2 has its positives, making it great for a single viewing, but its negatives make it an unnecessary rewatch.

3 REWATCH: BLACK PANTHER

The poster for Black Panther

Black Panther was a major win for big-screen, big-budget representation. The first superhero movie to feature an almost entirely Black cast, the film showed people of all races would turn out for a well-made superhero film no matter the color of the hero’s skin. Yet, the film is so much more than that.

While Chadwick Boseman’s T’Challa is charismatic and interesting, the best parts of the film are its trio of women, Shuri, Okoye, and Nakia, and its “villain,” Eric Killmonger. The different women represent various shades of complex femininity — a thrill for women everywhere. Meanwhile, Killmonger may be the bad guy in name, but he brought a perspective that made both the characters and audience think. It’s these elements that make the movie endlessly rewatchable.

2 ONCE IS ENOUGH: THE INCREDIBLE HULK

If there’s one movie that people forget is part of the MCU, it’s The Incredible Hulk, and for good reason. The animated Hulk lacked humanity and the movie overall was loud and superficial. While the action sequences are entertaining, the movie had few quieter moments of character development to balance them out.

Edward Norton is a great actor, one capable of quirk and heart, but all that was shoved aside in his turn as Bruce Banner/Hulk. As MCU fans know, in subsequent movies, Norton was replaced by Mark Ruffalo. Whether due to better writing, a different take on the character, or some of each, Ruffalo has had far more success in the role. Given the circumstances, this is arguably the only MCU movie that could be skipped entirely.

1 REWATCH: THE AVENGERS

the-avengers-first-movie

The first movie to bring together the superheroes from the various solo franchises Marvel was developing, The Avengers was a proof of concept. It showed that the shared universe of the MCU could work like gangbusters when executed well, and that fans would turn out in droves to see these characters team up.

The success of the movie hinges on the fantastic chemistry between the heroes as they learn to fight together instead of amongst themselves. It’s a great introduction to their team dynamic with a zippy plot to back it up. Plus, there’s the love-to-hate villain Loki, perhaps at his most devious and conniving, but also his most intriguing. It all adds up to rewarding repeat viewing.