One of the biggest mysteries set up by the Marvel Cinematic Universe is the origin of Knowhere, a giant decapitated head that doubles as a space station for the scum of the universe, and fans are now hoping that the impending release of Marvel’s Eternals may finally shed some light on the subject. First discussed as a possible Phase 4 film by Kevin Feige in April 2018, and later confirmed as such at San Diego Comic-Con 2019, the Eternals movie will supposedly span thousands of years, from the very beginnings of the Marvel Universe all the way to present day.

Directed by Chloé Zhao, Eternals will feature a new group of superbeings, more ancient and powerful than the MCU’s current host of heroes. The all-star cast includes Richard Madden, Salma Hayek, Angelina Jolie, Don Lee, Gemma Chan, and Barry Keoghan as the titular entities. As explained in Marvel Comics, the Eternals were seeded into humankind thousands of years ago by cosmic entities known as the Celestials - some of whom have already appeared in Marvel movies.

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One Celestial shown in Guardians of the Galaxy is Eson the Searcher, who is briefly seen in a vision of the past wielding the Power Stone. The Collector explains to the Guardians that "these stones... could only be brandished by beings of extraordinary strength." Another Celestial that has made the leap to the big screen is Ego, the Living Planet. In Guardians of the Galaxy Vol. 2, Ego tracks down his son, Star-Lord, after hearing of his feat in taking hold of the Power Stone and not dying horribly, something which would be impossible for a mere mortal. Ego provides a bit more information about his cosmic race when he explains to Peter that his first memory is of awakening afloat and alone in space. Over millions of years, he learned to manipulate the molecules around him, and eventually created the planet of which his consciousness is the core.

From wielding Infinity Stones to creating entire planets, the Celestials' enormous powers have been well-established in the MCU. Baed on what we've seen so far, it's clear that these beings are pretty difficult to kill - which only makes the prospect of a creature or person capable of rending Knowhere's head from his shoulders more enticingly mysterious.

Knowhere the Dead Celestial in Guardians of the Galaxy

Guardians Of The Galaxy Knowhere

Beyond these two entities, only one other Celestial has figured prominently into the MCU. Or rather, part of them has figured prominently - that being the aforementioned skull floating through space. It was first seen in Guardians of the Galaxy Vol. 1, when the Guardians take refuge inside of Knowhere, which acts as an immense spaceport and mining colony on the edges of the known Universe. Gamora explains that Knowhere is "the severed head of an ancient Celestial being." It is also home to Benicio del Toro's The Collector, who set up shop inside the head in order for his mining company to dig the organic tissue out of its skull, which apparently fetches a high price on the black market.

While all of this has conveyed the immense power and size of the Celestials, the only clue as to what could kill one has been Peter Quill's defeat of Ego, which was achieved by blowing up the his core. But who or what could be capable of decapitating Knowhere, who clearly had an enormous humanoid body and no Death Star-style design flaw to exploit? It is possible the answer to this query lies will be revealed in Eternals.

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Eternals Were Created by Celestials in the Comics

Eternals Tomb of the Space Gods

As depicted in the pages of Jack Kirby's original comics, the Celestials created the Eternals (and their evil counterparts, the Deviants) by experimenting on prehistoric humans. They also created mutants, which could be an easy inroad for the X-Men to join the MCU, but that's best left for another article. Suffice it to say, if the Eternals' true origin is shown on-screen, it will have to include an appearance by the Celestials - including, quite possibly, Knowhere itself.

Creation was not the extent of the Celestials' involvement in the Eternals' lives. During the group's short comic run, they were visited by their creators on a number of occasions, any of which could make the jump to live action. In fact, one set photo from the film depicts the City of the Space Gods, which is the location of the Cosmic Beacon of comic lore. This device's very purpose is to summon the Celestials to Earth. Most visits in the pages of Marvel have resulted in destruction and death, as the Celestials judge the actions of the Eternals and Earth's other inhabitants, and deem whether or not they are worthy to continue existing. They took part in the sinking of Atlantis, and they tangled with Thor and the Asgardians on more than one occasion. In fact, it is possible that the Celestials will be the primary antagonists in Eternals, as the film's villain is still being kept a secret by the studio. While the Deviants are arguably the safest bet to be the big bad, the Celestials are the far greater danger, should the Eternals fail to please them with a civil and prosperous planet upon their arrival.

How Knowhere Can Fit Into Eternals

Knull Kills Knowhere Marvel Comics

The most obvious sign of the inclusion of the Celestials in the Eternals movie has been their appearances in promotional materials for the film. Concept art distributed at this year's SDCC features the Celestials front-and-center, roaming across a planet's landscape, towering high above the cloud line. While none of them seem to be the Celestial that became Knowhere, a poster recently released for the movie depicts a Celestial with more than a passing resemblance to what might well have been Knowhere at one time.

The strongest argument against this being a picture of Knowhere is that the poster depicts a beam of light blazing from the creature's forehead, along with those shining from its eyes and nose. Knowhere, as the disembodied head that exists today, has no eye, nor any other orifice, on its forehead. But there is an easy explanation for this extra light. All of the Celestials (with the exception of Ego) have been shown as figures in full body armor, including intricate helmets. That light could simply be extra illumination provided by Knowhere's helmet, which has long since been stripped from the skull. This poster is by far our biggest hint that we will see the Celestial meet their violent end on screen at some point during Eternals.

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So, how exactly will Knowhere's death be depicted, should this mystery unravel during the movie? It is unlikely that the Marvel Comics version of Knowhere's death will be ported over. According to Marvel Comics canon (pictured above), the Dark God Knull was the one who severed the Celestial's head with the use of the cosmic sword, the All-Black. However, Knull is a symbiote, the same alien species as Venom, and Sony currently owns the movie rights to all of Marvel's symbiotes. An alternate version of Knowhere's death was told in the pages of Secret Wars, wherein Knowhere was depicted as a moon orbiting Battleworld. In that story, it was Dr. Doom who killed the Celestial. While it would be an extraordinary pleasure to see Doom's introduction to the MCU, Eternals was well into production by the time Disney bought Fox, so that is also a no-go.

It seems a wholly new death for Knowhere would be required for an on-screen portrayal in the MCU. The most probable explanation for Knowhere's decapitation is one where it was done for the greater good. As mentioned, Knowhere and the other Celestials represent a great threat to Earth in the case of their disapproval with the Eternals and their charge over the planet, and it has already been shown in the MCU that just two Celestials could spell the destruction of the entire Universe. This is why Ego sought out Starlord in Guardians of the Galaxy Vol. 2. With the extra power siphoned from his son, Ego was able to implement his "Expansion" - a.k.a. destroying all life in the Universe and remaking it to his own designs. Perhaps this is why Ego was the only surviving Celestial left in the modern day MCU; maybe all the other Celestials, including Knowhere, were killed to prevent the kind of cosmic cataclysm that was demonstrated in Guardians 2. It would certainly be the sort of Avengers-level threat that a movie like Eternals would need for a satisfyingly grand finale.

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