The Deep House

Ben and Tina, a young couple from New York, are engaged and excitedly embark on creating YouTube content. Their focus is on exploring infamous haunted locations, which serves as both their passion and a way to share thrilling experiences with their audience.

The couple travels to the picturesque countryside of south-west France in search of a notorious sanatorium that has reportedly sunk beneath an artificial lake. They envision a thrilling adventure but are met with disappointment upon discovering that the location has been transformed into a busy vacation resort.

Ben and Tina encounter a local named Pierre, who offers to guide them to a secluded part of the lake, buried deep within the forest of Chanteloup. He shares a mysterious legend about a mansion that has been preserved underwater since 1984 when the area was flooded.

Guided by Pierre, Ben and Tina dive into the lake and discover the surprisingly intact mansion that lies beneath the waters. However, the atmosphere is ominous, hinting at dark secrets hidden within its walls.

Once inside the mansion, the couple experiences a series of unnerving events. Disturbing voices echo through the halls, and their drone's motion tracker indicates unseen presences, causing paranoia to swiftly set in.

They stumble upon rooms filled with disturbing photographs, news articles about missing children, and cryptic satanic symbols. One door, ominously blocked by a crucifix, prevents them from entering a horrifying chamber filled with corpses masked grotesquely, suggesting a dark ritual context.

In a frantic attempt to escape, Ben and Tina discover that the window through which they entered has been sealed by a sudden brick wall. Panic begins to set in as they realize they are trapped inside this horror-filled mansion.

While trying to pry open a grate in the cellar, Tina is shocked by a sudden horrific attack, creating a deep emotional rift between her and Ben. This incident reveals the mansion's dark and violent nature, intensifying the tension between them.

Upon removing the masks from the corpses, Ben uncovers that they belonged to the Montégnac family, the mansion's former owners. This revelation deepens their horror as they start to realize they are entangled in a nightmare involving the family's sinister past.

The corpses of the Montégnac family animate and become hostile, actively pursuing Ben and Tina throughout the increasingly dangerous mansion. Their desperate situation pushes them to seek a way out, evoking primal instincts for survival.

As the couple attempts to flee via the chimney, the structure unexpectedly collapses, separating them from each other. This tragic event amplifies their sense of isolation and fear as the horrors intensify.

Ben uncovers a family tree revealing Pierre as the son of the Montégnacs, suggesting that he has orchestrated this horrifying encounter. This shocking twist complicates their situation as they realize they are pawns in a larger sinister game.

Ben encounters Sarah, the undead daughter of the Montégnac family, who possesses him and further complicates their desperate situation. This possession not only threatens Ben's life but also creates an emotional battle for Tina.

In a critical moment, Tina discovers a hidden exit within a chapel, leading her to hope for escape. However, chaos ensues when Ben, momentarily freed from possession, turns against her, culminating in a heart-pounding confrontation.

Despite wounding Ben in self-defense, their struggle ends tragically as Sarah fatally stabs him. As Tina escapes into the lake, she faces a final challenge and tragically drowns, highlighting the horrific cycle of terror in which they found themselves.

In a chilling post-credit scene, two divers arrive at the lake, echoing the haunting nature of the events that transpired. Their presence suggests that the cycle of terror continues, now with Pierre's lurking influence shaping the next victims.