Seth is a teenage boy who struggles with severe depression and social isolation. After dying by suicide, he awakens covered in strange conductive tape in a dusty, empty town. He carries overwhelming guilt regarding a traumatic childhood incident involving his younger brother. Convinced he is in a personalized hell designed to punish him, Seth cautiously explores his environment while piecing together fractured memories of his past.

Regine is a tall, heavy-set Black English teenager who woke up in the empty world months before Seth. She keeps her hair pulled tight across her scalp with a clip and often presents a tough, abrasive exterior. Having experienced severe domestic abuse in her previous life, she remains guarded but takes on a deeply protective role toward those she trusts.

Tomasz is a young Polish boy who claims to be 14 but looks closer to 11 or 12 years old. He has a spectacularly messy pile of hair that strongly reminds Seth of his younger brother. Having grown up in poverty and taught himself English by watching old movies, Tomasz uses old-fashioned phrasing and approaches danger with a dramatic flair.

Gudmund is Seth's bright, easygoing friend and secret romantic partner from the life Seth left behind. He is outgoing, well-liked by adults, and generally viewed favorably by his peers. Gudmund provides Seth with a crucial sense of belonging, though their hidden relationship creates complicated dynamics within their wider social circle.

Owen is Seth's younger brother. Following a traumatic kidnapping incident in England, he requires specialized care for neurological conditions. He shares a striking physical resemblance to Tomasz. The lingering impact of Owen's childhood trauma shapes the entire Wearing family dynamic and fuels Seth's immense guilt.

The Driver is a menacing, human-looking mechanical being clad in dark metallic armor who patrols the desolate English town. Armed with an electrified baton and operating from a massive prison facility, this relentless entity seeks to capture anyone wandering the abandoned city.

Candace is Seth and Owen's mother. She channels her underlying anger and repressed emotions into physical activities like running. Following the traumatic event involving Owen, she heavily favors her younger son and maintains a palpable distrust toward Seth's friends, leaving Seth feeling emotionally abandoned.

Edward is Seth and Owen's father. He copes with his family's lingering trauma by focusing intensely on various home improvement projects and taking medication. While he occasionally attempts to bridge the emotional gap with Seth, his avoidant tendencies leave his son feeling unsupported during crises.

Monica is part of Seth's core friend group in his previous life. She is socially active, confident, and harbors strong romantic feelings for Gudmund despite dating Harold. Her jealousy and unrequited feelings create severe friction within the friend group and directly impact Seth's social standing.

Harold, frequently called "H" by his friends, is part of Seth's close circle and dates Monica. He runs cross-country and generally goes along with the group's dynamics. He finds himself caught in the middle of the complicated emotional entanglements between Monica, Gudmund, and Seth.

Valentine is an escaped prisoner who broke into the Wearing family's English home when Seth was eight years old. He forces young Seth into an impossible situation, orchestrating a traumatic kidnapping that permanently shatters the family's stability.