Tenkyuu, a shinobi of the Arashi clan, desires a simple life, but after his grandfather falls ill, the dream of halcyon days is torn from him, and he reluctantly accepts the duties of a storm master. Using his blood talents and wits, he sifts through memories in the rain, bringing justice to those who have passed. A battle of wills is about to begin—man vs. nature—as Tenkyuu searches for his reason to become the next clan leader and the strength to endure the storm.