The Expanse guides viewers through a fractured humanity spread across the solar system, where discord reigns among Earth, Mars, and the Belters under the OPA's banner. Amidst this turmoil, the mysterious protomolecule emerges, intensifying tensions.

Before the protomolecule's emergence, the series delves into life on Ceres, where Joseph Miller, a disillusioned cop working for Star Helix, crosses paths with the enigmatic Juliette Mao, sparking a transformative journey.

Joseph Miller: The Complex Belter

Miller, a Belter himself, navigates a conflicted identity, striving to climb the societal ladder on Ceres despite being viewed as a traitor by his people. Assigned to find Juliette Mao, he embarks on a mission that transcends a mere investigation, leading to self-discovery and a quest for justice.

Juliette Mao: The Defiant Idealist

The daughter of a powerful family, Juliette rebels against her privileged background to champion the Belter cause. Initially misjudged by Miller as a rebellious figure, he later recognizes her unwavering dedication to the Belt's liberation, igniting a profound connection.

The Ultimate Sacrifice for Humanity

Miller's path converges with the crew of the Rocinante on Eros, where they unravel Juliette's tragic fate involving the deadly protomolecule. As they confront the looming threat, a sacrificial mission unfolds to avert catastrophe, showcasing bravery, selflessness, and a poignant connection that transcends life and death.