Charlie is a professor at Howard University with a passion for electricity and machines. Wrongfully incarcerated prior to the sudden shift in the world's population, he works to process his personal history while adjusting to the new society. He is driven to create a sustainable, visible power grid and seeks to connect with his estranged daughter.

Sidney is a 19-year-old multiracial woman raised exclusively by her white mother and stepfather. Isolated in her gated home in Wisconsin following the event, she strongly identifies as white and feels disconnected from Black culture. She is stubborn and determined to travel to Orange Beach, Alabama, to find her surviving aunt.

Vivian is a former singer and activist who serves as the queen of a newly established society in Mobile, Alabama. She possesses exceptional intuition and a strong desire to build a supportive community. Her leadership relies on empowering her people, encouraging them to tap into their history and personal passions.

Hosea is a former aspiring engineer who now serves as the king of Mobile alongside his wife. He is fascinated by science and historical achievements, using his knowledge to invent devices that channel energy. He frequently defers to his wife's judgment on major community decisions.

Nona is the confident and self-assured daughter of Vivian and Hosea. Acting as a princess in Mobile, she has discarded superficial societal expectations in favor of intellectual and spiritual pursuits. She takes an immediate interest in Sidney, offering her guidance and friendship.

Elizabeth is Sidney's mother, whose brief affair with Charlie resulted in pregnancy and a false accusation that sent him to prison. She provided Sidney with a comfortable life but maintained a profound, destructive silence about the past before the sudden onset of the event.

Agnes is Thomas's wife and Sidney's aunt, who relocates to the Orange Beach colony. Despite having Black ancestry, she fiercely identifies as white and adopts a cult-like "walker" ideology, encouraging others to drown themselves to reach heaven.

Tau is the oldest son of Vivian and Hosea. He is highly protective of his family and their new society, occasionally acting grumpy or dismissive toward outsiders who do not immediately align with their community values.

Herald is the middle son of Vivian and Hosea, possessing a brilliant mathematical and scientific mind. He focuses on developing sustainable energy systems for Mobile and collaborates enthusiastically with Charlie on technical projects.

Fela is the youngest son of Vivian and Hosea. He acts as a driver for the community and quickly forms a romantic connection with Sidney, helping her process her confusing feelings as she acclimates to the South.

Sailor is a cantankerous but skilled pilot and former member of the Air National Guard. Having served time in prison prior to the event, he now uses his aviation skills to transport people across the country, dreaming of starting his own airport in Mississippi.

Zu is Sailor's joyous and energetic child, who works at O'Hare Airport. Unconstrained by binary gender labels, Zu provides a vibrant contrast to Sidney's initial gloom during a tour of the bustling Chicago terminals.

Thomas is Elizabeth's brother and Agnes's husband. He plays a crucial role in Charlie's wrongful imprisonment by discovering Charlie and Elizabeth together and violently intervening to preserve social divisions.

Rick is Sidney's stepfather, an influential man who helped secure her college admission. He prefers Sidney to straighten her curly hair and represents the rigid expectations of the pre-event world.

Adam is one of Sidney's twin half-brothers. He and his brother walk into the lake alongside their parents during the initial wave of the mass drownings.

John is Sidney's other twin half-brother, who perishes in the lake with the rest of his immediate family during the sudden onset of the event.

Seraphin is a mystical conjure woman, or manbo, living in Mobile. She helps Charlie confront his suppressed anger and connects him with his ancestors through traditional spiritual practices.

Malcolm is a former Shakespearean actor recovering at the farm. He engages Sidney in philosophical conversations about trauma, normalcy, and the responsibility of those who maintained unequal systems before the event.

Ethel is a woman who survives the event and deliberately burns the surrounding land. She believes destroying the physical structures of cruelty is necessary to build a new life, offering Charlie a practical perspective on moving forward.

Little is a Black man who violently confronts Sidney at Agnes and Thomas's house. Charlie's intervention stops him, revealing him as a broken individual lashing out from deep-seated trauma rather than an organized threat.