While at his friend's home, Bon Namihira accidentally witnesses time travel in action and finds out that to keep it a secret, he must be erased.

While on a mission in A.D. 628 at the Tian Shan Mountains, Bon realizes that the group they're trailing inspired the epic "Journey to the West" tale

The crew warps to 490 B.C., saving lives at the Battle of Marathon. Later, Bon carelessly changes history and must take the place of an important herald.