Warning! Spoilers follow for Black Panther: Wakanda Forever.

With the recent release of Black Panther: Wakanda Forever and its treatment of Chadwick Boseman's passing, Marvel has once again shown it isn't afraid to tackle more adult themes within its popcorn movie parameters. Dealing with grief and loss is a higher abstract for a comic book-driven film and the Black Panther sequel certainly dives right into it.

It's not the first time Marvel has toed the line between family-friendly superhero thrills and potentially mature content. Marvel Studios have executed a fairly consistent balance between the two accounts for the franchise's continued popularity, but there have been several occasions that possibly challenged conventional expectations.

Terminal Illness

A split image of an ailing Jane Foster, T'Challa, and Meredith Quill from the MCU is shown.

Just like it is in real life, the Marvel Cinematic Universe has endured its share of losses stemming from being just plain human, subject to infections and diseases like anyone else. Two of Marvel's most recent offerings in 2022 showcase major MCU heroes incurring a terminal illness. In Thor's recent sequel Love and Thunder, Jane Foster battles a cancer diagnosis, until she discovers wielding Mjolnir might temporarily abate her symptoms.

Related: 9 MCU Quotes That Perfectly Sum Up Jane Foster As A Character

In the new Black Panther film, T'Challa passes away offscreen from an undetermined terminal illness despite Shuri's best efforts to save him. In the original Guardians of the Galaxy, Peter Quill's mother also passes away from cancer, shaping the space hero's destiny accordingly. It's heavy stuff for the same franchise that has Jeff Goldblum being a space techno deejay.

Marvel's First Nude Scene

An image of a naked blurred out Thor in Love and Thunder is shown.

It's a silly and gratuitous tongue-in-cheek one-off, but it's notable nonetheless. Taika Waititi and Chris Hemsworth's decision to give the people what they wanted was funny enough and it certainly revealed the extent to which Hemsworth keeps himself in shape to adequately render the Avenger's commanding physique.

Marvel audiences - particularly female Marvel fans - were thrilled to finally glimpse what they suspected all along about one of the world's sexiest men...yes, he's cut, and yes, he looks as good under the cape as outside of it, complete with a R.I.P. Loki tattoo on his back and setting up an infinite amount of internet Thor memes. Waititi even had several Zeus' court patrons, both male and female, faint at the sight of the strapping Norse god.

Mental Illness

An image of Steven Grant's Moon Knight is shown.

One of the more underrated successes in the 2022 docket of Marvel offerings was Disney Plus' Moon Knight, in which Oscar Isaac delivered an incisive, compelling portrayal of a reluctant superhero battling not only Arthur Harrow's forces of evil but also the difficulties of dissociative personality disorder. Moon Knight's three (so far) separate personalities of Marc Spector, Steven Grant, and Jake Lockley often found themselves at odds with one another.

Related: 10 Funniest Things That Happened In the Moon Knight Comics

Their diorama frequently resulted in the character dealing with memory lapses and losses of time as well as the severe anxiety and confusion brought about by such an invasive set of psychological circumstances. Not your typical Marvel subject matter and the MCU is a better place for it by adding more inclusive antiheroes.

Child Soldiers?

An image of Thor with powered Asgardian children is shown.

This particular segment in Thor: Love and Thunder proved to be decisively unpopular among more globally aware Marvel fans. Taika Waititi's script was likely innocuous in its arc of having Gorr the God Butcher's kidnapped Asgardian children to rise against their oppressor and help Thor fight Gorr's shadow creature forces with their newfound infused power of Thor.

Yet some patrons and critics found the idea of using children as soldiers, even Asgardian as they are, even within the bounds of the fictional Marvel Cinematic Universe, a bit too close to real-life use of children under the age of eighteen in military combat situations by nationalist fringe factions largely found in West and Central Africa.

Prostitution

An image of Kraglin and a Love Bot on the planet Contraxia is shown.

In hindsight, this sequence from the otherwise mostly family-friendly Guardians of the Galaxy Volume 2 is somewhat provocative if considered seriously. It's not often fans see the more tawdry or seedy sides of the MCU, especially within one of its comedy cornerstone franchises like Guardians, but here it was rendered down and dirty.

Related: 10 Facts Only Marvel Comic Fans Know About Adam Warlock

Yondu's Ravagers are enjoying some undoubtedly well-earned R&R on the planet Contraxia, availing themselves of the local cyberpunk brothel populated with what the MCU deemed 'Love Bots.' Yondu's first appearance in the sequel even has him zipping up his pants after utilizing the service at hand, a brief yet evident dip into more adult Marvel fare.

Torture

An image of the Black Widow teaser trailer is shown.

There's a shocking amount of torture depicted throughout the 39 Marvel movies and television series so far. Natasha Romanoff's conditioning in the Red Room was graphically shown both in Age of Ultron and her solo movie Black Widow. Bucky's memory wipes and brainwashing scenes are among the MCU's most difficult to watch.

Thanos tortured both Thor and Nebula via the Infinity Stones to get Loki and Nebula to talk, respectively. Ebony Maw torments Doctor Strange to give up the Time Stone on the Q ship in Avengers: Infinity War. Tony Stark's character was waterboarded in the first Iron Man. As is often the case in American media, it seems moments of graphic violence are considered more palatable for younger audiences than sexual content.

Enslavement

A picture of gladiator Thor in Ragnarok brandishing swords is shown.

Yet another common adult theme throughout both the Infinity and Multiverse Sagas, different forms of slavery and involuntary servitude appear frequently in the Marvel Cinematic Universe, most often in its 'conscripted' edition wherein heroes, antagonists, or entire populations are forced to do something for a higher power.

Related: The 10 Best Eternals Comic Book Storylines

It was shown to comic effect in Thor: Ragnarok when the Grandmaster shanghaied Thor into his gladiatorial arena games, and to more serious effects in Black Widow where young Russian girls were forcibly taken from their families and put in the Red Room. In The Eternals, the Celestials created both the title characters and the Deviants to serve them in perpetuity. Slavery is alive and well throughout the galaxy, unfortunately.

Genocide

An image of Thanos with young Gamora from Infinity War is shown.

It's happened so often now, these MCU end-of-the-world or end-of-the-universe stakes, that Marvel fans have become accustomed to the many levels of cinematic horrors that would otherwise be abhorrent in reality. Much of the time in the MCU it's the purple titan who's killing off entire populations in his quest to correct the universe's increasing needs, as seen here in one of the MCU's more cringe moments with a young Gamora just before his troops exterminate at least half of her world. But he's not the only one looking to wipe out the masses.

Ego had the same idea for different reasons in Guardians of the Galaxy Volume 2 as did the Celestials in The Eternals. Fictional portrayal notwithstanding, genocide is a taboo subject despite the fact it continues to occur all around the world.

Graphic Violence

A photo of Thanos strangling Loki in Infinity War is shown.

Modern movie audiences have grown extremely tolerant of explicitly rendered displays of all kinds of violence even within the relatively bloodless boundaries of the MCU. Yet there are a handful of scenes, events, and moments within the vast Marvel tapestry that push the envelope into the possible rated-R territory, like the one shown here when Thanos is graphically strangling Loki in the opening salvo of Infinity War, capping off the awful scene with a commensurately audible snap of the neck, much to Thor's agony.

The Winter Soldier's execution of Tony's parents in Captain America: Civil War was also an unusually brutal segment, as was Wanda's murdering of the alternate universe Illuminati in Doctor Strange: In the Multiverse of Madness.

Marvel's First Sex Scene

An image of Ikaris and Sersei making love in the Eternals is shown.

While Chloe Zhao's directorial debut in the MCU was widely trounced as one of the less compelling entries in the Phase Four roster, The Eternals did have the distinction of introducing Marvel's first true blue love scene. Audiences had seen plenty of innuendo and a few stolen kisses here and there (mostly by Tony Stark and Thor, and a minor and much-maligned flirtation between Romanoff and Banner), but nothing too overtly sexual.

Fans were largely underwhelmed by Richard Madden's Ikaris and Gemma Chan's Sersei coupling in the manner depicted by Zhao. Poor lighting, an apparent lack of heated passion, and no outright nudity were cited as detractions, but there was indeed some minor thrusting shown, which incited some Marvel families to quickly whisk their children away to the concession stand.

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