The story is set in a world with a continent split down the middle by a mountain range and a vast river. The eastern side is known as Roxche, and the western side is Sou Beil. The two sides have been at war for the past 130 years, though an armistice has been in effect for the past ten years. Wil, a young man from Roxche who enjoys reading books and has a photographic memory, is spending a leisurely summer vacation at his school's dormitory when his old friend Allison, a young girl his age who is now an Air Force pilot, arrives in a biplane to greet him after not seeing him for six months. The two take a drive together on Wil's motorcycle from school and run across an old man waiting on a bridge who is well-known in the area for telling false stories. They give him a ride to his home, and while there he tells them a story he claims to be true: that there is a treasure in the western region Sou Beil which could end the conflict between the warring regions. Before he can tell them more, a man who claims to be from the town hall takes the old man away, though Wil quickly notices that the man was most likely lying. Allison and Wil chase after them and find that the old man was taken away in a large plane. Allison and Wil steal a plane in order to find out where the old man was taken.

Allison and Wil successfully infiltrate the military base where the old man is being held, and manage to help him escape by giving him a hair pin for him to pick the lock on his jail cell. While getting away, Allison and Wil meet the lieutenant who Allison met six months previously who took interest in her. Allison and Wil manage to steal a sea plane while the old man holds back the enemy, but the old man causes an explosion right after the plane takes off, and is shot moments later. The lieutenant, Ker, is given the order to follow Allison and Wil and kill them if they attempt to cross the border; as a precautionary measure, another will follow to make sure Ker does not hesitate to follow his orders.

After Ker catches up to Allison and Wil, a dogfight ensues which ends with Allison shooting Ker with paintballs. Two other fighter planes catch up and try to shoot down both Allison and Ker, but Ker gets the better of them, shooting them down instead. Allison, Wil, and Ker make it to the cave where the treasure is and find it to be an ancient mural showing Roxche and Sou Beil sharing fire, signifying at one time the two cultures were at peace. Two officers from the Sou Beil army arrive and almost shoot Allison, Ker, and Wil, but Wil shoots first. This causes one of the officers to misfire on the cave roof, causing a cave in, killing both officers. The mural serves to end the war between Roxche and Sou Beil.