Watch VoirFilms. DH Productions' stable of knuckleheads are at it again with Chain Reaction 2. this time we storm through North America with a heavy metal onslaught of broken bikes, bones, and blood. three time Emmy Award winning producer/director Don Hampton throws you in the saddle for some kickass downhill madness that includes, the Winter X-Games, the NORBA and World Cup downhill circuit, urban street riding sessions, moto sized dirt jumping, skateparks and, of course, a butt load of painful crashes.