The two researched ancient Maya history, reading both creation and destruction myths, including sacred texts such as the "Popul Vuh." In the audio commentary of the film's first DVD release, Safinia states that the old shaman's story (played by Espiridion Acosta Cache, a modern-day Maya storyteller) was modified from an authentic Mesoamerican tale that was re-translated by Hilario Chi Canul, a professor of Maya, into the Yucatec Maya language for the film. He also served as a dialogue coach during production. As they researched the script, Safinia and Gibson traveled to Guatemala, Costa Rica and the Yucatán peninsula to scout filming locations and visit Maya ruins.