WARNING: The following contains spoilers for The 100 Season 6 episode "Red Sun Rising," which premiered Tuesday on The CW.

Although never actually appearing on screen in The 100's Season 6 premiere, the inhabitants of Alpha play a central role in the second episode, with their origins on the alien world revealed in the prologue. The presumed lost colony arrived on the faraway planet more than a century before the series began, in hope of finding a new home for humanity following the nuclear apocalypse that nearly destroyed Earth. The burgeoning colony dubs the planet "Sanctum," after the ancient Greek word for sanctuary, only to descend into bloody as the red sun eclipses.

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Despite this chillingly chaotic opening, humanity endured the horrors on Sanctum and thrived for several generations by the start of Season 6. One of the biggest subplots is what becomes of the lander that brought the Clarke- and Bellamy-led expedition to Sanctum. The masked hijackers attempt to stage a coup aboard the mothership, Eligius IV, and confine most of the awakened passengers to the mess hall before they are nearly wiped out by Raven Reyes, Charmain Diyoza and Madi. The three women quickly make two major discoveries about their would-be captors: They appear to have been a family, and their blood runs black.

The 100 - Red Sun Rising

The concept of black blood among certain survivors has been prevalent on the series since Season 3. Referred to as "Nightblood," the trait is a rare condition that allows some people to survive intense radiation lethal to most humans. The presence of Nightblood among the inhabitants of Sanctum is confirmed when the surviving hijacker is effortlessly able to pass through a protective force field upon her return to the planet's surface, completely unaffected by the radiation.

That suggests the crew of the Eligius III, in its initial attempts to colonize Sanctum, had its own set of unseen twists and turns, from developing Nightblood to maintaining proficiency in operating spacecraft, despite the decades they have been left to their own devices on the planet. While being able to survive, the brazen attempt to hijack the Eligius IV implies that the descendants of the Eligius III crew are desperate in escaping from Sanctum. And this implication is compounded by the final scene's twist.

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As the expedition from the Eligius IV recovers from the effects of Sanctum's eclipsed red sun, they are approached by the inhabitants of the makeshift village they stumbled across. Not only is Clarke surprised to see the inhabitants are still alive, as the abandoned village had suggested something ominous had occurred, but that the approaching group is comprised entirely of children. And to confirm the hijackers' desperation to escape Sanctum, the first thing the children ask Clarke is if they are here to take them away.

The 100 has faced many opponents over the previous five seasons including warrio,r factions living in the wilderness, the affluent living on the blood of the young, a malevolent artificial intelligence, and escaped convicts. In Season 6, the characters have suddenly found themselves confronted with a new faction of survivors primarily consisting of children.

The 100 returns on the CW for its sixth season on April 30 at 9 pm ET/PT. The series stars Eliza Taylor, Paige Turco, Marie Avgeropoulos, Bob Morley, Henry Ian Cusick, Lindsey Morgan, Richard Harmon and Tasya Teles.