Execution is everything when it comes toMarvel movies, as many of the franchise’s most promising films and TV shows have sadly turned out to be duds despite their strong concepts. Thebest Marvel movieslive up to the potential of their loglines, realizing exciting stories with competency and creativity. However, there have also been some painful missed opportunities among the comic company’s long history of live-action adaptations, ruining what might have been an interesting idea on paper.

Granted, there are some bad Marvel movies or series that were ill-conceived from their very ideas, such the first comic book movie based on a character that never had her own titled comic run,Madame Web. But a movie or a TV show with a promising idea that simply falls flat is always worse to bear. Be it due to bad writing, poor adaptations of classic characters, orthe MCU’s trademark uneven special effects, many Marvel projects simply fall short of their goals.

Nick Fury leaving Earth in Secret Invasion

It’s rare for the Marvel Cinematic Universe’s audience to so definitively unite against a single project, with even the franchise’s worst films having at least some defenders. But it seems that absolutely no one was impressed bySecret Invasion, far and away considered to be theworst MCU Disney+ show. The series gives Samuel L. Jackson’s Nick Fury his long-awaited solo project, detailing his efforts to stop the subtle invasion of shape-shifting Skrull aliens.

Secret Invasionis based on the crossover Marvel comic arc of the same name, which is still a beloved event in the canon of the source material. Sadly, what deserved to be a huge event on the level of the Infinity Saga was watered down into a small espionage thriller for Nick Fury to tackle on his own. With baffling retcons, boring visuals, bland writing, and some of the most egregiously bad special effects the MCU has seen,Secret Invasionfell fall short of the adaptation’s potential for greatness.

Sergei Kravinoff in a yellow room in Kraven the Hunter

9Kraven The Hunter Having A Solo Movie Was A Genuinely Promising Movie Concept

Kraven couldn’t save the Sony movie universe

The Sony Spider-Man universe sans Spider-Man himself was an ill-conceived idea from the start, even if Tom Hardy’sVenomtrilogy was an entertaining enough flagship. Projects likeMorbiusorMadame Webmay have been destined for failure, based on obscure characters that wouldn’t excite general audiences enough to show support, but the series had another potential trophy withKraven the Hunter.The Aaron Taylor-Johnson-led star vehicle centered on the Spider-Man villain Kraven, a hunter in search of dangerous prey.

Kraven the Huntercould have been an exciting tale in the style ofThe Most Dangerous Gamechronicling Kraven’s attempts to best heroes and villains higher and higher in the food chain. Sadly, Sony’s annoying need to have their central “villains” as sympathetic and heroic as possible eliminated anything interesting about Kraven as a character, turning him into a generic lethal superhero. Add in the most strained allusions to Spider-Man yet without actually featuring the webslinger’s presence, andKraven the Huntertook the Sony universe out with a box office whimper.

Kang the Conqueror looking angry in Ant-Man and the Wasp Quantumania

8Ant-Man & The Wasp: Quantumania Was Set To Introduce The MCU’s Next Thanos

Only to fail to measure up

Ant-Man & The Wasp: Quantumaniawas arguably the Marvel Cinematic Universe’s first real make-or-break point that utterly failed at what it was trying to do, putting an entire multi-film arc for the franchise in jeopardy. The third Ant-Man movie saw Scott Lang and company shrink down to more miniscule sizes than ever before, unlocking access to the mysterious and alien Quantum Realm. It’s here that Kang the Conqueror, first alluded to inLoki, reared his head as the next big bad of Thanos-level importance.

Sadly,Ant-Man & The Wasp: Quantumaniasuffered from tonal issues, unfunny jokes, and some of the most cheap-looking over-reliance on green screens and CGI the MCU had ever displayed. The introduction of what could have been a powerful and interesting villain falls completely flat in the wake of his defeat at the hands of Ant-Man, putting a need to have the hero win above the health of the franchise as a whole. It’s no wonder that the series has quietly rolled back Kang’s importance, swapping him out forRobert Downey Jr.’s Doctor Doom.

Captain America with sidewinder and the Leader in Captain America Brave New World

7Captain America: Brave New World Should’ve Been Sam Wilson’s Triumph

But boxed him in to a generic personality

The latest release from the Marvel Cinematic Universe,Captain America: Brave New Worldhasn’t been the definitive win the series was hoping for, suffering from a very mixed critical and public reception. The fourth Captain America movie officially passes the mantle from Chris Evans' Steve Rogers to Anthony Mackie’s Sam Wilson, formerly The Falcon. In his first outing as Captain America, Sam has to unravel the intricate schemes of an old villain in order to clear his mentor’s name and save the newly-elected President Ross.

Anthony Mackie’s bombastic personality and comic cleverness has always been a huge asset to his time in the MCU, and giving him a solo movie could have finally allowed his lovably cocky attitude to soak up the spotlight. Sadly,Captain America: Brave New Worlddulls Mackie’s lusterby making him uncharacteristically straight-laced throughout, overshadowed by the plot in some misguided attempt to lend seriousness to his new role as Captain America. That’s not even to mention the film’s controversy problems thanks to its overt political themes.

the smiling tiger in the falcon and the winter soldier

6The Falcon And The Winter Soldier Could’ve Been A Great Buddy Cop Show

But kept Sam and Bucky apart for far too long

Part of what made Anthony Mackie’s career in the MCU so entertaining has been his chemistry with Sebastian Stan, who plays Bucky Barnes, a.k.a. The Winter Soldier. Bucky and Sam’s bickering and banter quickly became one of the best parts ofCaptain America: Civil War, and their actors' off-screen chemistry seemed like a lay-up for a buddy cop show putting them front and center. It seemed as thoughThe Falcon and the Winter Soldierwas ready to do just that, only to fall far short of expectations.

In truth, there are small glimmers of this promise throughout the series, with Sam and Bucky’s therapy sessions, snide comments at one another on the job, and their ultimate ability to work in tandem as superheroes making up the best parts of the show. Sadly,The Falcon and the Winter Soldierkept Sam and Bucky at a great remove for far too much of the show’s runtime, with neither of their separate parts outshining them as a whole. The series also wasn’t helped by a poorly-written finale and the awkward handling of its villains.

Thor and Korg in Thor Love and Thunder

5Thor: Love And Thunder Wasted Many Promising Elements

Director Taika Waititi quickly earned a lot of good will with MCU fans afterThor: Ragnarok, which revived the Thor solo movies in the eyes of many after the low point that wasThor: The Dark World.This makes it all the more surprising that his follow-up film,Thor: Love and Thunder, was such an absurd disappointment despite the many ripe opportunities for the series it offered. WhileThor: The Dark Worlddidn’t even have a strong premise to stand on,Thor: Love and Thunderhad no excuse for its failures.

Christian Bale was excellent as the deicidal Gorr the God-Butcher, and bringing back a much peppier Natalie Portman into the fold as The Mighty Thor would have been a brilliant way to allow a Thor to exist as both a hero on Earth and a spacefaring cosmic warrior. Sadly, both new characters were killed off far too quickly for the MCU to capitalize on them. What’s left in their absence is a cringeworthy mess of out-of-place humor and horrendous CGI that represents not only a terrible MCU film, but the worst movie inTaika Waititi’s filmography.

Jean Grey floating in space in Dark Phoenix

But failed even with the benefit of hindsight

It’s hard to say if the foundations for a good story were ever there inX-Men: The Last Stand, the infamously bad conclusion to the original Fox trilogy ofX-Menfilms. One of the movie’s most egregious sins was the watering down of the famousDark Phoenixstoryline from the comics, removing the cosmic elements of the story and rushing the outcome. With the benefit of hindsight, it seemed as though the new timeline’s take on the same story had the potential to live up to the lofty standards of the original story.

Despite having solid source material and a great cast of hungry young stars,Dark Phoenixutterly fumbles the chance to finally do justice to one of the X-Men’s most important stories. Although the comic accuracy of the Phoenix itself is higher than that of the first attempt, the sheer sense of tiredness and by-the-numbers plot development made it clear that Fox was simply counting the days until the MCU merger went through with this film. Generic villains, so-so performances, and an absurdly rushed finale all smeared Fox’s second chance at getting the storyline right.

jamie bell as the thing in fantastic four movie (2015) looking offscreen

32015’s Fantastic Four Turned The Beloved Team Into Something Else Entirely

When a director has no love for the comic book source material

The early 2000sFantastic Fourmovies certainly had their problems, but at the very least they had an understanding of the dynamic that made comics' first superhero family so compelling in the first place. With the ability to learn from the previous duology’s mistakes and improve upon what worked, Josh Trank’s 2015 reboot should have been a layup. Talented, recognizable stars like Michael B. Jordan and Miles Teller only made the second take on the famous powered quartet that much more exciting.

Unfortunately, Trank wasn’t interested in satisfying fans. His version of The Fantastic Four was more of a dour, depressing body horror movie with a few half-hearted comic book elements thrown in just to maintain the rights to the characters. The movie somehow messes up Doctor Doom again, needlessly tying him to the Four themselves, and the cast’s disturbing lack of chemistry isn’t indicative of their acting skill. Hopefully,the upcomingFantastic Four: First Stepscan finally make things right.

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2Black Widow’s Solo Movie Left Much To Be Desired

For a founding Avenger, she deserved better

Admittedly, it was quite a strange move for the Marvel Cinematic Universe to only give Scarlett Johansson’s Black Widow a solo project after she had already died in-universe. But there’s no time like the present, and the less-than-ideal timing wasn’t a surefire promise that the long-awaited solo film for the founding Avenger would be bad. In fact, with a deeper exploration of Black Widow’s origins, new characters like Taskmaster and Red Guardian, and the same spy-thriller bent that madeCaptain America: The Winter Soldierso great, there was a lot to be excited about forBlack Widow.

Tragically,Black Widowwould turn out to be a massive exercise in wasted potential. The talents of high-class actors like Florence Pugh and David Harbour were profoundly mishandled, and the movie featured one of the most disappointing portrayals of a Marvel Comics character ever with its flavorless take on Taskmaster. PerhapsThunderbolts*can better redeem some of the characters who firt appeared inBlack Widow, but it can’t undo the film’s rushed final act, terrible special effects, and forgettable storyline.

Smiley Man attacking in The New Mutants

1The New Mutants Missed On X-Men Horror

Making the whole movie a strang exercise

The New Mutantsmay have turned out to be one of the strangest exercises in superhero brand recognition ever. Quietly releasing a film in 2020 during the throes of the COVID pandemic with a brand-new cast despite the writing being on the wall for Marvel’s takeover was an odd move forthe Fox X-Men timeline, to say the least. But surprisingly, the bones for an interesting X-Men movie were certainly there forThe New Mutants.

Promising a horror film with mutants,The New Mutantshad the benefit of talented young actors like Anya Taylor-Joy, Maisie Williams, and Charlie Heaton. The concept of a genuinely frightening scary movie featuring superheroes was also a novel concept that hadn’t really been done before. ButThe New Mutantsmuddled its star-studded cast with poor direction and confused the horror tone into more of a drama with some creepy elements, making for one of the most bizarre and misinformedMarvel moviesto ever release.