"Punk" follows Peter (Vince Staples), who, after receiving a disheartening rejection letter, takes off on a road trip with a crew of free-spirited runaways. Headed by Skip (Colson Baker a.k.a. Machine Gun Kelly) and his sister Lucy (Cara Delevingne), they collectively push the boundaries of freedom, risking life and limb to train-surf along the breathtaking fault lines of North America. After falling for Lucy, Peter soon discovers that the crew that once took him in are a band of bank robbers, hell-bent on becoming modern-day Robin Hoods.