When hundreds of people inexplicably disappear in an isolated area of the Mississippi River where Elly Thompson grew up, she relives the mysterious disappearance of her own father on the river when she was five ... an event she witnessed but didn't comprehend.
Now a documentary filmmaker, the strong-willed Elly takes a camera crew (including her sarcastic ex-lover) to investigate. Neglecting to inform her companions about her own history with the river, she hires a laconic, life-long river man named Jack - who finds himself drawn to Elly - to navigate them through the dangerous waters. As the elements become increasingly harsh, the group is trapped by the remote and desolate landscape. One by one, their own fears and demons preying upon them, each begins to break down. Now Elly is struggling to hold them all together as the secrets of what happened Beneath the Mississippi all those years ago are slowly ... and irrevocably ... revealed in this taut and disturbing psychological-thriller.