幕末、財政難に苦しむ越前大野藩の藩主土井利忠と、下級武士から家老へと引き立てられていった内山七郎右衛門との絆を中心に物語が描かれる。利忠の意を汲みそこなうと白扇が飛んでくる。飛んでくることを承知で、七郎右衛門は自分の意見をはっきりと伝える。そうやって、ふたりで窮地に陥った大野藩の舵をとっていく。
The novel centers on the bond between Doi Toshitada, the lord of the Echizen Ono domain, which was struggling financially at the end of the Edo period, and Uchiyama Shichiroemon, a low-ranking samurai who eventually become a chief retainer. Whenever retainers failed to read Toshitada's intentions, a white folding fan would come flying at them. Knowing well that it might, Shichiroemon still spoke his mind openly. That was how the two of them worked together, steering the Ono domain through one crisis after another.
七郎右衛門最大の功績は商い（屋号を『大野屋』という）を軌道に乗せたことだ。武士が商売を始めるなど非常識にもほどがある時代。七郎右衛門の柔軟な発想を利忠はしっかり見抜いていた。名君と才能ある家臣。問題は山積、反対派もいれば障害もごろごろ。それを乗り越えていく過程が爽快だ。
Shichiroemon's greatest achievement was getting a business venture, run under the name "Ohnoya", successfully off the ground. In an age when it was considered outrageous for a samurai to engage in commerce, this was nothing short of radical. Toshitada clearly saw Shichiroemon's flexibility and practical intelligence. A wise lord and a capable retainer faced with endless problems, fierce opposition, and obstacle after obstacle. Reading them overcome these challenges is deeply satisfying.
＊nothing short of radical: 急進的以外の何ものでもない⇒非常識なほど斬新
この物語は史実に基づいている。黒船来航を経て大きく時代が変わった。多くの藩が借金に苦しむ中、大野藩藩主だけは暮らしにこまることはなかったという。
This story is based on historical fact. After the arrival of the Black Ships, the times changed dramatically. While many domains struggled under heavy debt, it is said the lord of the Ono domain never fell into financial hardship.