Sanna is the 21-year-old daughter of a rich landowner in southern Sweden. Her father, Bengt, makes his fortune by leasing his vast expanse of inherited land to hardworking family farmers, many of whom struggle to make ends meet. Stern and unyielding, Bengt holds influence over those less fortunate, while Sanna struggles with the idea of becoming his heir apparent. When she begins a relationship with Marcus, the penniless son of a nearby farmer, her father issues an ultimatum — leave Marcus or lose her inheritance.
Soon after, Bengt disappears without a trace. Without a body or little else to go on, police turn to Tanja, an investigator with Missing People Sweden, whose passion for solving the case quickly turns into obsession.
Based on true events and envisioned by award-winning director Gustav Möller (The Guilty, Sundance Film Festival 2018), The Dark Heart is a suspense-laden story of love, greed, and power that utilizes the almost mythological landscape of the Swedish countryside to set a dark and ominous tone of what lies beneath the soil.