The Marvel Cinematic Universe reached its peak with the Avengers movies, which brought together Earth's Mightiest Heroes to fight several world-ending and, eventually, universal threats. Each movie is thrilling, entertaining, funny, action-packed, and unforgettable, largely thanks to sharp writing, an instantly iconic ensemble of characters, and assured direction.

Still, no one can deny some Avengers movies are more enjoyable than others. Whether because of their streamlined narrative, humor, action setpieces, or importance within the universe's larger story, some movies in the Avengers series have a higher rewatch value. Hardcore fans will undoubtedly revisit them often, but even casual fans might find themselves rewatching them every so often, enjoying them just as much as they did the first time.

5 'Avengers: Age of Ultron' (2015)

Directed by Joss Whedon

Everyone pretty much knows Avengers: Age of Ultron is the weakest film in the saga. Building up on Phase 2 of the MCU, the plot sees Tony Stark (Robert Downey Jr.) and Bruce Banner (Mark Ruffalo) building a powerful AI, Ultron (James Spader), who soon becomes sentient and begins a plot to take over the world. Aided by the "enhanced" twins Wanda (Elizabeth Olsen) and Pietro Maximoff (Aaron Taylor-Johnson), Ultron launches a full-scale attack against Earth's Mightiest Heroes.

Age of Ultron is the worst Avengers movie by a considerable margin. It's overblown, oddly paced, and far too simplistic compared to its predecessor and successors, giving the titular team very little to do. Spader is a worthy addition to the cast, bringing his unique brand of creepy allure into the voice role, but Ultron is just too weak and underdeveloped to stand alongside Loki and Thanos. To make matters worse, writer/director Joss Whedon is not up to the task of adapting one of the Avengers' best comic book storylines, reducing it to its bare minimum and resulting in a lifeless and occasionally boring entry into the saga. There is no reason to revisit Age of Ultron beyond Wanda and Pietro's arrival, and considering the latter dies before the credits roll and the former has a lot more development in future MCU projects, the film is among the most skippable in the Infinity Saga.

4 'The Avengers' (2012)

Directed by Joss Whedon

2012's The Avengers kickstarted the MCU as fans know it today. The plot sees Loki (Tom Hiddleston) launching a full-scale invasion of Earth by stealing the Tesseract and using a scepter to control the minds of several key players in the world. With the fate of the world at stake, Nick Fury (Samuel L. Jackson) assembles a group of heroes, including Iron Man, Captain America (Chris Evans), and the exiled Bruce Banner.

Bringing Earth's Mightiest Heroes together on the big screen seemed like an impossible task; after all, no one had ever attempted to build a cinematic universe of this proportion. Alas, The Avengers succeeded by finding the perfect balance between lighthearted humor, jaw-dropping action sequences, and emotional development for each member of its large ensemble—even if Natasha is the best Avenger in the movie by a lot. Over a decade since its release, The Avengers still feels fresh and relevant, thanks to the perfect dynamic between its titular team and a considerably appealing villain. The film is highly enjoyable and quite rewatchable, with many of its best bits becoming ingrained in the pop culture lexicon. The third-act battle for New York's fate is also among the best final battles in Marvel, taking the time to explore each of the Avengers in action without feeling slow or stale.

3 'Captain America: Civil War' (2016)

Directed by the Russo Brothers

The first film in Marvel's Phase 3, Captain America: Civil War is the last entry in Steve Rogers' trilogy. The plot sees Steve's former friend, Bucky Barnes (Sebastian Stan), framed for an attack on the UN, launching an international manhunt for him. Meanwhile, following a mission gone wrong in Lagos, the governments of the world attempt to enforce strict oversight of the Avengers, leading to two opposing factions led by Steve Rogers and Tony Stark, respectively.

Captain America: Civil War is a great movie, balancing countless threads without ever succumbing to the weight of its ambitions. While technically not an official Avengers movie, Captain America: Civil War has four of the six main Avengers, plus pretty much every member of their supporting cast and a few worthy additions. Civil War was the first time fans had seen such a large crossover, with the film bringing together more heroes than ever before. It introduced Spider-Man and Black Panther to the MCU and expanded the roles of key figures like Wanda, Vision, and Winter Soldier. In many ways, Civil War is as much an Avengers movie despite not having the word on its title. It's also extremely rewatchable, especially the now-iconic airport battle, an extended sequence that sees Cap and Iron Man's teams go toe-to-toe in a brilliant fight that expertly showcases every character's abilities.

2 'Avengers: Infinity War' (2018)

Directed by the Russo Brothers

After years of hints, Avengers: Infinity War finally introduced Thanos (Josh Brolin) in all his glory. The plot follows the Mad Titan as he travels the galaxy to gather the six Infinity Stones to reshape the universe to his liking. The conflict brings together every main character in the story, with Earth's heroes mounting a last-minute defense to protect Vision's Mind Stone while Iron Man, Doctor Strange (Benedict Cumberbatch), and the Guardians of the Galaxy take the battle to Thanos himself.

Thanos is the best villain in the MCU by far, and Infinity War is a showcase for Brolin's acting, giving the Mad Titan the spotlight and allowing him to steal the titular team's thunder. The film is narratively complex and emotionally satisfying, featuring many of the MCU's most powerful moments, from Vision's sacrifice to the now-famous final sequence where half of the characters are "dusted." Although Infinity War is the best Avengers movie, it's not the most rewatchable, largely because it's half of the story. Still, it remains one of the saga's most enjoyable efforts, featuring larger-than-life action and an emotionally resonant story that leads to one of the most infamous endings in modern cinematic history. Infinity War finds the MCU at the peak of its powers and influence, and it remains entertaining six years after its debut.

1 'Avengers: Endgame' (2019)

Directed by the Russo Brothers

Following the shocking ending of Avengers: Infinity War, Avengers: Endgame finds the survivors trying to rebuild their lives without all those that vanished. However, when Ant-Man (Paul Rudd) escapes the Quantum Realm, he brings a dangerous but potentially viable idea to the table. The remaining Avengers assemble for the fight of their lifetimes, attempting an ambitious "time heist" that turns Earth into the stage for the final battle for the universe's fate.

Avengers: Endgame was the end of Marvel's glory days, and it very much feels like both a victory lap and a swan song. The film is massive in scope and outright monumental, bringing closure to a decade of continuous storytelling with a thrilling story that seamlessly balances easter eggs, fan service, and satisfying narrative choices. Essentially a hectic and over-the-top heist movie, Avengers: Endgame is incredibly rewatchable, especially to hardcore Marvel fans and all those who long to revisit the franchise's days as pop culture's dominating force. From its time-hopping antics to its climactic battle to the bittersweet ending, Avengers: Endgame is arguably the most rewatchable movie in the Marvel Cinematic Universe, an impressive feat, considering the company's super-sized slate.

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