Orion is an aspiring writer with a severe heart condition, living in the Bronx. Having lost his parents in the September 11 attacks, he signs up for Death-Cast to ensure he never misses a chance to say goodbye to his loved ones. He is naturally cautious and acutely aware of his mortality, but he desperately wants to experience life outside his health-related fears.

Valentino is a muscular aspiring model who just moved to New York City to start a fresh life. His conservative parents stopped speaking to him after he came out as gay, prompting his cross-country relocation. He is deeply devoted to his twin sister, Scarlett, and signs up for Death-Cast wanting to ensure he and his sister are prepared for unexpected tragedies.

Dalma is an aspiring app programmer and Orion's adoptive sister. She lost her father to cancer when she was three and subsequently bonded with Orion over their shared childhood grief. She is intensely protective of Orion's health and constantly monitors him for signs of cardiac distress.

Joaquin is the ambitious creator and founder of Death-Cast. He guards the secret of how the company predicts deaths closely, sharing it only with the government. He firmly believes his service will change the world by allowing people to tie up loose ends and live their final days intentionally.

Frankie is an abusive husband and Valentino's landlord. He works as a photographer and sees the launch of Death-Cast as an opportunity to exploit people for financial gain. He aggressively seeks to locate a Decker to photograph them during their final hours.

Gloria is a mother living in an Upper East Side apartment building with her abusive husband, Frankie, and their young son. She desires stability and independence, secretly signing her entire family up for Death-Cast to maintain a sense of control over their unpredictable lives.

Scarlett is Valentino's twin sister and an aspiring photographer. She recently survived a severe car accident, an event that left her with lasting anxiety about dying alone. She supports her brother unconditionally, acting as his anchor when their parents reject him.

Rolando is a herald for Death-Cast who struggles with the emotional weight of delivering fatal news to callers. He carries a long-standing torch for his college friend, Gloria, and worries constantly about her safety with her husband.

Paz is Gloria and Frankie's young son, an aspiring child actor who recently booked a commercial. He is deeply affected by the tension in his home and expresses a fear of Death-Cast to the new tenant.

Naya is Joaquin's wife and a key figure in the development of Death-Cast. She specifically designed the psychological support systems for the company's heralds, insisting that human beings, rather than automated systems, deliver the news of a caller's impending death.

Dr. Emeterio is a cardiologist at the hospital treating Orion. Unlike his previous doctors, she sees the potential utility in Death-Cast's warnings and works to facilitate complex medical decisions based on the new service's predictions.

Férnan owns a pawn shop that is looted during the riots surrounding the Death-Cast launch. He struggles to connect with his son, Rufus, but is inspired to improve his family relationships after an encounter with a Decker.

Rufus is Férnan and Dr. Emeterio's son. He often clashes with his father but bonds with him over a new bicycle gifted to him by a stranger passing through their shop.

Olivia is Rufus's sister and the daughter of Férnan and Dr. Emeterio. She participates in family outings to the park and enjoys imagining the lives of strangers on the subway.

Dayana is Dalma's mother and Orion's guardian. She was best friends with Orion's mother and stepped in to raise him after the September 11 attacks, providing him with a stable and loving home environment.

Floyd is Dalma's father and Orion's adoptive guardian. He is protective of his family and assists with navigating the medical and logistical challenges of Orion's heart condition.

Dahlia is Dalma's younger sister and Orion's adoptive sister. She actively participates in welcoming Valentino to their home, showcasing the family's warmth.

Mateo is a shy young boy who struggles to make friends. Raised by a single father after his mother died in childbirth, he lives with a persistent fear of death separating him from his remaining parent.

Teo is Mateo's supportive and encouraging father. He raises his son alone and tries to teach him that love is a superpower, helping Mateo navigate his social anxiety.

Clint is an elderly Decker originally from Argentina. He meets with Rolando at a café on his End Day and shares stories about his life and his mother's domestic struggles.

Harry is an airline captain who locks himself in the cockpit after receiving a Death-Cast call, grounding the flight and altering the travel plans of the passengers onboard.

Alano is Joaquin and Naya's son. He is thrilled to be awake for the midnight launch of his father's company.

Andrea is a herald for Death-Cast who views her job pragmatically. She advises her colleagues to detach emotionally and stop thinking of the Deckers as people in order to work more efficiently.

William is a photographer who originally planned to shoot Valentino's modeling session. He goes to Times Square to document the Death-Cast launch and secretly plans a proposal to his girlfriend.

Christi is William Wilde's girlfriend, completely unaware that he intends to propose to her during their outing.

Laverne works at a modeling agency and informs Valentino about his postponed photo shoot. She dismisses his Death-Cast warning as mere hysteria, comparing it to the Y2K panic.