Disgraced noblewoman Catherine disguises herself as a male squire named "Cai" to compete in the Royal Tournament, hoping to win an audience with the king and clear her father's name. She shocks everyone by winning her first joust, drawing the attention of the undefeated champion Roland—who recognizes her family's fighting style and, through a practice duel, discovers her true gender and identity. Meanwhile, Lord Gideon—the corrupt lord who framed her father—grows suspicious and sends men to investigate and eliminate her. Roland secretly trains Catherine, revealing that he long doubted the treason verdict and has been quietly uncovering the truth. Gideon sets a trap, planting a stolen royal dagger in Catherine's quarters to frame her; Roland shields her from arrest. Catherine finds a secret letter from her father, uncovering clues about Gideon's illegal weapons smuggling. But when Gideon mandates bloodline checks for all tournament participants, Catherine's disguise is suddenly on the brink of exposure.
