Usagi and friends helps a spirited teenage girl named Kayley who wants to be a knight of the round tabke in Camelot like her father Sir Lionel, and their companion, a blind young man named Garrett who lives in solitude and their quest to find Excalibur.
Young Kayley and her mother Julianna see her father Lionel off to Camelot for a meeting with King Arthur and his knights of the round table, Kayley expressing to become a knight when he promises her a trip to the kingdom someday. However, a dark-hearted knight named Ruber becomes upset at his share of the land's divisions and attacks Arthur to usurp him. The knights repel Ruber's attack, but Lionel is killed before Arthur defeats Ruber with his sword Excalibur. Despite her father's death, Kayley grows into a young woman, dreaming of her chance to prove herself and become a knight like her father, much to her mother's chagrin who believes it to be too dangerous for her. Some place around Usagi and friends arrive and introduce themselves to Kayley and Julianna
Ten years later, a Griffin breaks into Camelot and steals Arthur's sword, subsequently being attacked by Merlin's silver-winged falcon named Ayden, causing the griffin to lose the sword in the Forbidden Forest as he escapes. That night, Ruber returns and kidnaps Julianna, Kayley and the team, plotting to use them to sneak into Camelot and overthrow Arthur by using a magic potion which combines his allies (and a chicken dubbed Bladebeak as a demonstration) with various weapons and instruments of destruction. Kayley and the team manages to escape and goes to the forest in search of the sword, Bladebeak being ordered to follow her and report her location to Ruber. While there, Kayley and the team meets Garrett, a blind hermit who has learned the ways of the forest and survives with ease with the assistance of Ayden the silver winged falcon that belongs to Arthur's wizarding adviser, Merlin. Despite his initial objections, Garrett allows Kayley to help him recover Excalibur. Coming across Dragon Country, the pair meet a conjoined twin dragon; the sophisticated and intelligent Devon, and the crude but loyal Cornwall who are bullied by the other dragons due to their smaller size and their inability to spit fire or fly. With their help, they manage to escape a dragon attack and a chase by Ruber who has caught up to them. Over the course of their adventure, Kayley teaches Garrett to rise above his pain from the past when she mentions Sir Lionel. Garrett tells her that long ago, he was accidentally blinded by horse in a fire at Camelot, but Sir Lionel trained him.
Soon they come across the scabbard of Excalibur, but Kayley and Raye's insistence on questioning Garrett causes him to miss a key signal by Ayden and he is injured by Ruber. Ruber and his party are delayed by moving trees, allowing the pair to escape. While tending to his wound, Kayley and Garrett develop an attraction toward one another as the magic of the forest heals him. Trailing Excalibur to a giant ogre using it as a tooth pick they manage to steal back the sword use the ogre to again delay Ruber's attempts to overtake them. Exiting the forest with Excalibur, Garrett gives it to Kayley to turn in herself, no longer feeling a part of that world. He returns to the forest with Ayden, and Kayley and the sailor scouts are captured moments later by Ruber and his thugs. Devon and Cornwall inform Garrett of this and they rushes to rescue them. Ruber uses the potion to meld Excalibur to his own arm and using Kayley as a bargaining chip, Ruber forces Julianna to gain them entry to Camelot. However, Kayley frees herself (with the help of Bladebeak) to warn them and a fight breaks out. Garrett, Devon and Cornwall arrive and assist, Cornwall and Devon finally learning to work together find out how to fly and quickly turn the tide of the battle in their favor.
Confronting Ruber who tries to kill an injured Arthur, Kayley and Garrett manage to kill Ruber by tricking him into stabbing the sword into the stone from which it was pulled. The conflict of magic destroys Ruber, disintegrating him, and heals those injured in the fight as well as returning Ruber's minions and Bladebeak to normal. Cornwall and Devon are separated, but decide to rejoin in their reignited friendship. Afterward, Arthur realizes that the strength of his kingdom is not in the strength of its king alone, but the strength of its people and he knights both Kayley and Garrett for their valor. Afterward, the team watches Kayley and Garrett dance at their knighting ceremony and share their first kiss, which signifies at a strong and close blossoming romantic relationship before they ride off on a horse with "Just Knighted" as a sign on the back as the pair of them ride off together.