Atlas is a 14-year-old aspiring mountaineer named after the Greek Titan. He climbs alongside his father but carries deep, unaddressed anger regarding his mother's death. He struggles to maintain focus during emergencies, often freezing in fear when faced with sudden danger on the mountain.

Maddie is an American teenager accompanying her father on international climbing trips. She openly admits her fear of heights and lacks technical mountaineering experience. Despite these physical limitations, she brings a grounded and emotionally open perspective to the team.

Chodak is the main Sherpa guide leading the British expedition up Mount Everest. He possesses deep respect for Chomolungma and understands the lethal realities of the terrain. He maintains a calm, authoritative presence, prioritizing the safety of his clients over their ambitions.

He is a professional cartographer and dedicated mountaineer who continually seeks new summits. He attempts to bond with his son through extreme physical challenges rather than open communication. He maintains strict expectations for safety but allows his own ambitions to drive the expedition forward.

Mr. Thomley serves as the official leader of the Everest expedition. He brings a pragmatic, realistic approach to the dangers of high-altitude climbing and expects strict obedience from the team. He carries the heavy responsibility of managing both the mountain's hazards and the conflicting personalities of his crew.

Mr. Blake is a wealthy and arrogant member of the climbing party. He frequently ignores essential safety protocols and dismisses the expertise of the Sherpa guides. He carries a private notebook and holds political views that create immediate friction within the camp.

Mr. Levinsky is a principled Jewish climber joining the Everest expedition on the eve of World War II. He pays close attention to the rising political tensions in Europe and refuses to tolerate bigotry from his climbing partners. He struggles with a severe cough but tries to hide it to remain with the team.

Mrs. Thomley supports the Everest expedition from afar. She operates the radio communications, relaying crucial weather forecasts and international news regarding the impending outbreak of war in Europe.

Mr. Pierson is an American mountaineer who travels globally with his daughter. He previously climbed in Austria, where he encountered Atlas during a moment of crisis on the trail.

Atlas's mother is a former climber whose deteriorating health forces the family to relocate from Britain to Utah. She leaves a lasting impact on her son, who carries a scarf she knitted for him as a tangible reminder of her presence.

Atlas's grandfather is a grounding family figure who delivers tragic news to his grandson. He offers early, difficult advice about accepting grief and finding a way to carry on with life.

Sonam is a local Sherpa who travels the upper reaches of the mountain. He communicates primarily through gestures and utilizes traditional Tibetan symbols to explain concepts of inner peace.

Mr. Schäfer is a German operative who attempts to gain access to Mount Everest and Tibet under the guise of scientific investigation. His historical connections to the Nazi party create lingering suspicions among the British climbers.