The god Wotan gives the young Prince Sigmund of Valhalla and his sister Brunhilde, the leader of the Valkyries, the task of defending the Petrified Forest. This is threatened by the Vikings (led by the aggressive Hunding), who plans an invasion of the forest in search of the secret treasure of the Nibelung, the possession of which gives one unlimited power. After crossing the border and invading Valhalla, Hunding finds an ally in the daughter of one of Sigmund's loyal followers, Erika, who is embittered by unrequited love. She helps the Vikings raid the camp of the Valhalla residents and kill many warriors. Sigmund swears vengeance and pursues them with the remaining men. However, thanks to other traitors in Sigmund's ranks, Hunding succeeds in capturing him and his fiancée Siglinde, Erika's sister. At the end, Sigmund escapes and, with the help of the Valkiries, succeeds in stopping the invaders and defeating Hunding in a duel.

Der Wikingerfürst Hunding aus dem hohen Norden will den sagenumwobenen Nibelungenhort und das magische Walhallaschwert in seinen Besitz bringen, das seinem Träger uneingeschränkte Macht verspricht. Im Auftrag des Gottes Wotan werden der Schatz und das Schwert in den Tiefen des versteinerten Waldes aufbewahrt und vom mächtigen Nibelungenherrscher Sigmund und der Walküre Brunhilde bewacht. Als Hunding und seine Krieger auf ihrer abenteuerlichen Suche in den Wald vordringen, kommt es zur unausweichlichen Konfrontation zwischen Nibelungen und Wikingern…

Un esercito vichingo deve attraversare la foresta pietrificata per sottrarre ai custodi Sigmund e Brunilde la spada d'oro e il tesoro dei Nibelunghi.