What compels a man to beat the shit out of his fellow man? Some excellent cinema has been made of this fundamental question, from crowd-pleasers like Rocky to muckrakers like Fight Club. Now, in a Collider exclusive trailer reveal, we can see how Jungleland aims to emotionally add to this conversation, promising exacting, desperate performances and a sensitively beating heart. From co-writer and director Max Winkler (Flower), Jungleland stars Jack O'Connell (Unbroken) as a bare-knuckle boxer named Lion, and Charlie Hunnam (The Gentlemen) as his brother and trainer named Stanley. Stanley owes money thanks to a …