Warning: SPOILERS ahead for Jupiter's Legacy.

Netflix series Jupiter's Legacy introduces a new world of superheroes, while also gradually unveiling their origin story through its 1920s/1930s storyline. It isn't until episode 7 of Jupiter's Legacy season 1, "Omnes Pro Uno," that the six people who will become the original Union of Justice finally receive their powers.

Based on the comics by Mark Millar and Frank Quitely, Jupiter's Legacy was adapted for TV by Steven S. DeKnight. Its story is split between the period setting of the Union's origins and a modern day storyline, in which their children - many of whom are now superheroes themselves - struggle with their parents' expectations and the pressures of living up to their legendary feats. The kids' powers were inherited genetically, but the original six members of the Union of Justice had to go through a gruelling series of trials to prove themselves worthy.

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Like the comics, Jupiter's Legacy avoids offering too much exposition about the beings that gave the Union their superpowers. Even after the full origin story is revealed, there's still plenty that's left up to the audience's imagination. That said, here's a breakdown of what Jupiter's Legacy reveals about the Union's mysterious benefactors, and how it differs from the comics.

Sheldon's Messages & The Island's Purpose Explained

Jupiter's Legacy Sheldon Alien Patterns

Sheldon Sampson's visions begin shortly after he watches his father commit suicide in response to the Wall Street Crash of 1929. He experiences blackouts and seizures, and is plagued by the gruesome ghost of his father's while simultaneously experiencing visions and a compulsion to draw strange circular patterns. The ghoul that Sheldon is seeing isn't actually his father; rather, it's a vision sent to test his conviction and strength of character by taunting him, planting doubts in his head, and trying to turn him against his loved ones. The beings on the island are simultaneously guiding Sheldon towards them and testing his mettle by pushing him to the brink of insanity and darkness. While this may seem cruel, it's designed to measure whether or not he's worthy of the superpowers he'll eventually be given.

The island also chooses five other candidates by making them appear in one of Sheldon's visions. Like Sheldon, they're all flawed people who nonetheless have great potential. Fitz stood up for Sheldon against angry laid-off factory workers, showing both leadership and temperance. Walt bore the burden of his father's terrible secrets and shielded his brother from them. Grace stood her ground as the only female reporter in a 1920s newsroom. Richard is a doctor who got caught in the island's storm while on a mission carrying out volunteer work for the Red Cross. And George was the first person to believe in Sheldon's visions, and to support his plan to search for the island.

The difficulty of the journey to the island and the challenges of trekking across it were all designed to test the six chosen candidates both individually and as a group. This culminates in the final test, where they are seemingly trapped with no way out and begin to turn on one another. The skeletons scattered around this final testing area reveal that many groups of six people have been brought to the island over the centuries, and some failed to prove themselves worthy, instead falling to in-fighting and killing one another. The island is both a physical and a psychological obstacle course - one that the six members of the Union eventually manage to overcome.

Related: Jupiter's Legacy Season 1 Ending Explained

How The Union Get Their Powers & From Whom

Jupiter's Legacy Alien Symbols

After figuring out that they need to work together to overcome the island's final challenge, the six members of the Union open a glowing doorway that leads them to what looks like an alien planet (possibly Jupiter). There they find a strange glowing colored structure, where the island's inhabitants are waiting for them. They don't appear in their true form, but instead appear as people that the chosen heroes most want to see - like George's mother, Fitz's grandmother, and Sheldon and Walt's father. The beings congratulate the six humans for overcoming their trials and burdens, and reward them with superpowers and shiny new uniforms.

While it's not made explicit, the beings on the island fit the profile of being ancient, godlike aliens who may even transcend time and space. They possess great psychic powers that allow them to reach out across the planet to identify potential candidates for receiving powers and guide them towards the island, as well as the ability to create the living storm that surrounds the island. These powers could be interpreted as incredibly advanced technology, but the beings could also be entirely magical in nature. Given the title of the series, it could be theorized that they're the gods of the Roman pantheon - like Jupiter, Juno, Mars, Apollo and Vulcan - and that each god gave different powers to the members of the Union. For example, The Utopian getting his powers from Jupiter, king of the gods, would explain why he's the most powerful member of the team. And it would certainly be fitting if Brainwave got his powers from Janus, the two-faced god.

How Jupiter's Legacy's Power Origin Compares To The Comics

Jupiter's Legacy Comics Origin Aliens

The Union of Justice's origin story in the Jupiter's Legacy comics is similar to the TV show, with Sheldon Sampson's visions guiding him on an expedition to the island with a group of chosen companions. However, Sheldon's visions are clearer and he has a better idea of what to expect from the island in advance. After they pass through the door and emerge on what appears to be another plane of existence, Sheldon tells his friends that it is a "university." The beings that they meet there do not taking human form and are overtly alien in their appearance, standing at around 8 feet tall with green skin and white robes.

The Jupiter's Legacy comics similarly avoid going into too much detail about who these beings are. The story was inspired by Roman mythology, and therefore there's little need to over-explain the exact nature of the Union of Justice's superpowers or the creatures that gifted them. Ultimately what's important is the effect that the powers have on the people who received them, and not where they got them from.

More: Jupiter's Legacy Season 2: What To Expect