In the Forland Kingdom, Dr. Akamashi stages a rebellion with his beastly army and robotic minions, overthrowing the monarchy. Before his demise, the king urges Princess Alita to flee and rendezvous with her brother Prince Kaito for safety and a chance to reclaim their realm. During her escape, a twist of fate intertwines her destiny with Falis, a notorious bounty hunter, as they swap bodies. Now inhabiting each other's forms but retaining their unique abilities and personalities, they strike a pact: Alita-in-Falis vows to restore order to the kingdom, while Falis-in-Alita accepts the challenge, birthing the enigmatic Murder Princess. Together, they face not only the task of regaining control of the kingdom but also the unraveling of a complex web of intrigue that threatens their world.