In the 17th century Japan is divided between two forces. The eastern army lead by the Warlord Tokugawa Ieyasu and the western army which fights for Toyotomi's clan. Despite wining a recent battle, things look grim for the eastern army. Toyotomi's army has a supply of modern firearms, a weapon which might turn the tides of war. Tokugawa Ieyasu send his trusted samurai Mayeda and his son Yourimune to Spain. There they are to purchase 5000 muskets. But it's a dangerous journey and there are many who plot against them. And when they finally arrive in Spain, nothing goes the way they expected.