Fia spends her whole life trying to prove she's good enough, then dies proving she isn't, and wakes up remembering she was already legendary. That collision between the underdog knight grinding for validation and the dormant Saint who already won everything breaks the entire setup in the best way. By the time she realizes what she actually is, the show has already made you care about the girl she was pretending to be.

Fia trains relentlessly to become a knight and prove herself worthy of her family's legacy, despite lacking the natural talent her relatives possess. On the day she is meant to slay a small demon, she finds herself facing a dragon and suffers a deadly wound. As her life flashes before her eyes, she remembers a past existence as a powerful Saint in a bygone era who defeated the Demon King. That former life ended in pain because of who she was, leaving her afraid of ever becoming a Saint again. Now the magic of her previous life has been rekindled, and it could make her a stronger knight than she ever dreamed. Remembering the danger of being discovered, Fia vows to stay on the path of knighthood and keep her powers secret, though resisting such useful abilities proves hard. The result is a fantasy action adventure about a reborn Saint hiding in plain sight.