Long ago, Loki and Odin swore an oath of brotherhood. Since then, Loki believes that it is enough to love one soul, and wreak havoc on all else, until he learns that he is the one who will be responsible for bringing about the Twilight of the Gods. In a desperate attempt to forestall Ragnarök, Odin betrays his brother and forces him to take a bride. A Valkyrie, someone who will be loyal to Odin, and doubtless keep the god of lies in line. But if Odin believes that Loki will be controlled by the whims of one woman, then he is terribly mistaken. Sigyn has never regretted the decision she made to leave behind her life as a mortal princess to serve Odin as one of his Valkyries, until now... When Odin orders her to marry Loki, Sigyn feels trapped by her duty and the oaths she swore. Even worse, to marry means that she will no longer be a Valkyrie, and she will lose all immortality that comes with it. Tricked during his wedding vows, Loki finds himself exiled to Midgard and bound to a mortal. Now he must keep his new bride alive long enough to find her a new form of immortality or risk being dragged into death with her. Sigyn seeks to find a new purpose after everything that she once believed in betrayed her. Allying themselves to great mortal heroes, they set out to slay a dragon, claim a legendary treasure, and unite kingdoms. All the while, seeking to discover the truth to the question that could change their lives forever-what makes one worthy of becoming a god?