Seventeen-year-old Ruby is a Fireblood: she can create flames and spread heat thanks to the magical powers she is endowed with from birth. However, in a kingdom where the Icebloods rule, and her own people are brutally persecuted, the girl is forced to hide her fiery gift, otherwise she faces death or imprisonment. Unfortunately, Ruby's origins cannot be kept secret, leading to the death of her mother while trying to protect her daughter. Terrible grief forces Ruby to leave her native village and seek revenge. She no longer wants to hide and vows to do everything to overthrow the hated Ice King from the throne. While Ruby prepares to carry out a difficult plan, she unexpectedly finds a loyal ally among the Icebloods. The mysterious young man becomes not only a mentor and close friend for her... But do they have a common goal? And can they get along? After all, not a single love story between Iceblood and the Fireblood girl had a happy ending...