At 17, Su Wangshu is a dock apprentice. When he takes half a bloodstained telegram under the guns of Japanese agents, he is swept into the currents of his age. Old Gu's abacus opens the door to his awakening, while his father's blood debt brands him with the will to resist. From a race against death at the Shanghai docks to a clash of codes in Nanjing's secret tunnels; from the fateful choice of 30,000 people in a Chongqing air-raid shelter to a deadly numerical trap in Beiping that he turns against its makers.
He rewrites supply reports with his abacus beads, making Japanese ammunition grow legs and run to the resistance bases. He exploits Sato's superstition to lay a trap that leads puppet troops to rebel after taking a wrong turn. And with secret messages hidden in his fountain pen, he cuts a path to safety for his comrades through the sea of fire. Shen Qinghe once held a gun to his temple, but in the end, her weapon and his abacus beat in unison. The cross of the Meng siblings and their abacus beads piece together the same path to survival amid the smoke of war.
The scar on his forehead is a medal he recovered from the flames, and the mended abacus holds the hopes of millions. When the broadcast of victory rings through Beiping, he runs his fingers over the beads and says to the empty air, "Old Gu, look. The books are settled."
From the struggle to survive to the defense of peace, the weight of a single abacus bead carries the answer a generation worked out with their lives: every scar grows roots that reach for the light, and every sacrifice becomes a path beneath the feet of those still living.
It's well-written, with lots of details! Worth reading further.