Wrestler Mark Schultz, overshadowed by his more charismatic and successful older brother, Dave Schultz, both Olympic gold medalists, struggles to form his own identity in the world of competitive wrestling. When the wealthy and eccentric John du Pont, a wrestling enthusiast and heir to the du Pont family fortune, approaches Mark with an offer to sponsor him, providing state-of-the-art training facilities on his private estate, Mark sees an opportunity to step out of his brother's shadow. Du Pont presents himself as a paternal figure and mentor, aiming to lead the US wrestling team to glory at the upcoming World Championships and Olympics while fulfilling his own craving for greatness and patriotic pride.

As Mark trains under du Pont’s patronage at the Foxcatcher estate, he begins to flourish, finding a sense of purpose and belonging. However, the relationship between the benefactor and the athlete grows increasingly complex as du Pont's erratic behavior and need for control manifest. When Dave eventually joins the team at du Pont's behest to serve as a coach, the dynamics shift. Dave’s presence challenges the tenuous bond between Mark and du Pont, leading to an untenable situation fraught with tension, jealousy, and an uncomfortable dependency that threatens the stability of all involved. The story unfolds in an atmosphere thick with ambition, desperation, and the haunting pursuit of the American Dream.