In June 1828, a ship arrives at the Irish port town of Cove - on board, seven brutally murdered crew members and passengers. Three apprentices, two sailors, and the eleven-year-old son of the shipowner survived the massacre, while the captain has vanished. Even before the official investigation, the famous Arctic explorer and theologian William Scoresby has the opportunity to speak with all the survivors and witnesses. Gradually, the statements reveal a complete picture of the horrific events, yet the eerie case remains mysterious: Who is lying? Who is telling the truth? Was the crew of the Mary Russell involved in a murderous plot, or were the seven men victims of a madman? The investigations lead Scoresby into an abyss of doubt, superstition, and midnight illusions. Seven Lights is based on a true story, one of the probes.