Stacy is a young American woman enjoying a trip to Mexico before she and her friends head to graduate and medical school. She is highly image-conscious, opting to wear sandals without socks on a strenuous jungle hike. Initially, she relies heavily on her best friend Amy for emotional grounding and defers to others for decision-making. Though uncomfortable with unfamiliar situations, she is forced to confront her passive nature as the group's journey into the jungle progresses.

Jeff is a pragmatic pre-med student who acts as the de facto leader of the American friend group. Rooted in problem-solving and logic, he firmly believes that preparation and intelligence can manage any situation. He organizes the trip to the ruins using a basic travel guide and a hand-drawn map, prioritizing efficiency and structured plans over the hesitations of his friends. He immediately establishes rules and strategies when the group faces physical adversity.

Mathias is a German tourist searching for his missing brother, Henrich, who disappeared after following an archaeologist to a remote excavation site. He is stoic and observant, carrying a quiet intensity that unsettles some of the Americans. Despite being a stranger to the core group, his practical mindset makes him a key contributor to their efforts in navigating the jungle. He believes focusing on basic instincts is the best way to handle high-stress situations.

Eric is a young American tourist on vacation who tends to be impulsive and self-indulgent. He begins the difficult jungle hike hungover and unprepared, often avoiding responsibility and relying on others to make decisions for him. His immaturity positions him as one of the more vulnerable members of the group when faced with physical danger. He easily gives in to panic and paranoia when isolated.

Amy is a pre-med student and Jeff's girlfriend, characterized by her emotional intelligence and optimism. She acts as the social glue for the group, frequently providing emotional support to her best friend Stacy. However, she struggles with denial, repeatedly attempting to maintain a positive outlook and assuming that external help will resolve their problems, even when confronted with obvious warning signs.

The Mayan villagers inhabit a remote settlement near a hidden path. They are deeply suspicious of outsiders and refuse to communicate with the tourists in either English or Spanish. Acting as armed guardians of the jungle, they aggressively warn travelers away from certain areas, operating with a harsh logic to contain the threats hidden within the ruins.

Pablo is a Greek tourist who adopts a Spanish nickname since the Americans cannot pronounce his real name. Because he speaks neither English nor Spanish, he relies entirely on gestures and enthusiasm to communicate. Eager for adventure, he serves as the group's theoretical connection to the outside world because he leaves a copied map for his two Greek friends to follow.

Henrich is Mathias's brother whose disappearance initiates the entire journey. Against Mathias's advice, he insisted on following a woman he had fallen in love with to a remote excavation site near Cobá. He left behind a hand-drawn map that the tourists use to trace his steps into the jungle.

Juan is one of the three Greek tourists who repeatedly crosses paths with the Americans during their vacation. Unable to speak English, he is assigned a Spanish nickname by the Americans. He remains behind at the resort when his friend Pablo leaves for the jungle, serving as a potential future lifeline.

Don Quixote is the third member of the Greek tourist group. Like his friends, he does not speak English and is given a Spanish nickname by the Americans. He stays behind at the hotel, serving as the group's hope for an eventual rescue once they find Pablo's copied map.