Set in the land of Orsterra, the Order of the Sacred Flame believed their world was created by thirteen deities before twelve were forced to seal the fallen god Galdera, who refused to relinquish what they created, within the afterworld that can be accessed through the sealed Gate of Finis. The player follows the stories of eight heroes as they journey through Orsterra: Ophilia, a cleric of the Sacred Flame whose pilgrimage brings her into conflict with a cult headed by an apostate named Mattias; Cyrus, a scholar and teacher at the Royal Academy seeking a missing tome of dark arts called From the Far Reaches of Hell that was stolen by Headmaster Yvon and his assistant Lucia; Tressa, a merchant who goes on a journey after acquiring a journal detailing a past adventurer's travels; Olberic, a former knight of the Kingdom of Hornburg seeking purpose after his kingdom was destroyed in an attack by a sellsword named Werner; Primrose, a dancer and former noble seeking revenge against the Obsidians, a criminal organization that murdered her father; Alfyn, a traveling apothecary inspired to take up his trade after a stranger saved him from a fatal disease as a child; Therion, a thief tasked by a noble family to recover a set of dragonstones belonging to them; and H'aanit, a hunter tracking the monster Redeye after it petrified her mentor.
After progressing through all the characters various stories, the heroes' quests become intermingled as Mattias, Lucia, the Obsidians, and Werner are all revealed to have been under the employ of the immortal witch Lyblac. Revealed to be Galdera's daughter, Lyblac orchestrated the acquirement of From the Far Reaches of Hell and the dragonstones, along with the destruction of Hornburg, to unseal the Gate of Finis while using the Obsidians as her personal army to eliminate threats like Primrose's father. Lyblac required Graham Crossford, the man who wrote Tressa's journal and saved Alfyn as a boy, as an ideal vessel for Galdera to gain corporeal form due to his bloodline's ties to the god; Graham escaped from her clutches, but was mutated into Redeye. This forced Lyblac to seek out Graham's only living son Kit to complete the ritual. After tracking down the Gate's location in Hornburg, Lyblac fully resurrects Galdera and is absorbed into him. The eight heroes fight a vicious battle against Galdera, sealing him back into the afterworld and saving Kit, who receives closure with his father's spirit.