MCU: Eternals Writers Clarify Thanos Confusion With Brother Eros (Exclusive)

By Russ Milheim Updated:
Marvel Eternals, Thanos

Warning - This article contains spoilers from Eternals .

Fans now have an entirely new set of heroes to love: the Eternals. Introduced in Marvel Studios’ recently released film, the group are god-like beings tasked with protecting humanity.

Despite being entwined with humankind for thousands of years, they couldn’t be further from those they protect.

At one point in the movie, the Celestial Arishem drops a bombshell: none of the Eternals are organic—they are all synthetic beings created by him to observe and serve.

Out of all the Eternals introduced, there is a specific one whose arrival drew more attention than the others: Eros, brother of Thanos. But then a question arises: if Eternals are synthetic beings, how would someone like Thanos have a brother?

How Can Thanos Be Eros' Brother?

Thanos Eros

Speaking in an exclusive interview with The Direct, Eternals screenplay writers Ryan and Kaz Firpo tackled a tricky question: how can Eros have a brother if Eternals establishes that his kind is synthetic?

Kaz teased that “there’s a couple of answers, neither of which we can confirm or deny:”

“I feel like there’s a couple of answers, neither of which we can confirm or deny. Is Thanos not a synthetic being? How do we know? How do we know Thanos is not an Eternal?"

Ryan took over to establish some of those possibilities. The first is that there may have been “a planet where organic Eternals lived:”

“I would also say that I think that there’s a version where the Eternals that they send to other planets are synthetic beings, but perhaps there was at one time, a planet where organic Eternals lived. Maybe Eros is one of those…"

Another possibility is that the Eternals in which the film follows are actually “synthetic beings that are copies of organic beings somewhere else:”

“…[Maybe] the ones that we’re seeing on these other planets, who were sent on these missions, who are essentially put into these loops basically that they keep reliving the same experience over and over, maybe those are synthetic beings that are copies of organic beings somewhere else.”

Kaz chimed in to note how he likes the idea of learning “that Thanos retroactively was actually frikin’ synthetic all along.”

“Two potential doors for you to step through. I like the idea of… what if we learn that Thanos retroactively was actually frikin’ synthetic all along. These seem like a couple great episodes for What If…?.”

Thanos: Synthetic or Organic?

Thanos Titan

When a character walks into the MCU landscape and claims to be the brother of the being who erased half of existence, there's no way it won't lead to some mind-bending mythos additions—not to mention status quo shifts.

Eros' existence alone presents so many questions, ones that will be truly exciting to explore going forward.

Looking at the evidence, it's probably a safe bet to say that Thanos, at least the one audiences followed, is organic. Why? Well, he bleeds. In Eternals, not a single one of them shed any blood. When they die, they simply go gray and become shells. Fans saw Thanos' decapitated head.

One of the more intriguing ideas that Ryan Firpo brings up is the possibility of there being organic versions of all the Eternals that viewers got to know over the course of Zhao's epic—their original body could be out there in the cosmos somewhere, waiting to be found.

Fingers crossed that Marvel Studios gets on these Eternals sequels sooner rather than later, as there is an endless string of ideas that are begging for exploration.

Until then, fans should probably head back to the theaters and give Marvel Studios' latest release another watch.

- About The Author: Russ Milheim
Russ Milheim is the Industry Relations Coordinator at The Direct. On top of utilizing his expertise on the many corners of today’s entertainment to cover the latest news and theories, he establishes and maintains communication and relations between the outlet and the many studio and talent representatives.