In a secluded valley in Iceland, Gummi and Kiddi live side by side, tending to their sheep. Their ancestral sheep-stock is considered one of the country’s best and the two brothers are repeatedly awarded for their prized rams who carry an ancient lineage. Although they share the land and a way of life, Gummi and Kiddi have not spoken to each other in four decades. When a lethal disease suddenly infects Kiddi’s sheep, the entire valley comes under threat. The authorities decide to cull all the animals in the area to contain the outbreak. But Gummi and Kiddi don’t give up so easily – and each brother tries to stave off the disaster in his own fashion: Kiddi by using his rifle and Gummi by using his wits.

Friends Sveppi and Villi discover that an old nemesis has built a doomsday machine that can trigger earthquakes and volcanic eruptions. With the help of their friend Gói, they manage to sneak into his evil lair. But this is only half the battle - to save the country they'll have to destroy the machine.