Henry Alex Rubin and Dana Adam Shapiro's documentary delves into quad rugby. The fast and hard sport combines elements of rugby, basketball, roller and demolition derbies, as the players bring pit crews to maintain their tricked-out wheelchairs during matches. Conceived in Canada as "murderball" (then renamed wheelchair or quad rugby), the sport is now organized into international competitions. MURDERBALL is organized to highlight three interrelated storylines. Mark Zupan's background emerges slowly. He was injured in a car accident in 1993. Three years later, he was playing rugby. Passionate, devoted, and supported by his girlfriend, Zupan has found a sense of order and focus in the sport. Similarly committed, Joe Soares is a onetime U.S. star cut from the team when he began to slow down. Frustrated by what he perceived as rejection, Soares started coaching for the Canadian team. Keith Cavill was injured in a motocross accident. His story reveals another angle on quad rugby, in that he enters the film at the start of his recovery, finding in the sport a way to channel his energy and depression. As if to underline this point, the film ends with the players meeting a group of injured Iraq War veterans.