‘What is rugby?’: New film Brothers on Three documents the game at West Point

With unprecedented access to one of the top US college programs, director Sean Mullin uncovers raw stories of love and loss

At the United States Military Academy at West Point, rugby has the best winning record of any men's sports program. Brothers on Three, a new documentary about the team out this week, begins with scenes of wild joy from Houston, Texas in 2022, when the Black Knights beat St Mary's, from California, to win their first US college title.

And yet director Sean Mullin's film is shot through with loss.