A scientist known as Dr. Akamashi launches a coup d'état in the Forland Kingdom using his army of beasts and two android minions. With his dying breath, the king tells his daughter, Princess Alita, to escape at all cost and find Prince Kaito - her older brother who's currently on a diplomatic mission abroad - in order to guarantee her own safety and possibly take back the kingdom.

As Alita flees, however, she ends up in a predicament that results in her dying and swapping bodies with Falis, an infamous bounty hunter who happened to be out hunting in a nearby forest together with her monster sidekicks, Dominikov and Pete. With the two women retaining their respective skills and personalities but changing appearances, Alita, now in Falis's body, begs her to go back to her kingdom and make things right, offering her body and soul as collateral - to which Falis, now in Alita's body, agrees, leading to the birth of the so-called Murder Princess, who ends up not only having to take back and protect the kingdom, but also, unravel a much deeper intrigue that soon unfolds.