Metalocalypse is a flash animated comedy that follows the exploits of a fictitious half American – half Scandinavian death metal band known as Dethklok. The band with its lead vocals Nathan Explosion are very popular, but incredibly stupid – a death metal version of Spinal Tap. The band enjoys a popularity level unheard of in reality, ranking as the fifth largest global economy by the end of the season 2. Dethklok concerts are so notoriously dangerous that those attending are required to sign “pain waivers” at the entrance and fans will do anything that band and its songs tell them to, even if that means death, which is usually the case. The show has been picked up for a season 4 which is now airing.
Dethklok is notified of a looming secret that has been around for hundreds of years: the secret of the Metalocalypse. Before they can contemplate what this means, however, Nathan must give a eulogy and do the most brutal thing he has ever done: get in touch with his emotions.
Dethklok breaks up and is about to give their final performance. As they prepare for the show, each member of the band are deciding their post-band careers. Meanwhile, Selatcia takes this time to make his attack.
As Dethklok hosts the most important dinner of their career, the divvying of album credits, over tagging on social networking sites, and fights over a girl come to head. Can CFO keep their issues in check? Will the record executives forgive them for the past year of mistakes? Or will it be a total, brutal disaster?
The guys spend time on a sub without women, and the conditions quickly deteriorate, prompting Pickles and Nathan to compete for the affections of their producer.
Murderface goes to Mexico for plastic surgery after he receives a dubious award. The rest of the guys, meanwhile, deal with the effects of aging and years of hard living.