Computer programmer and self-proclaimed recluse Monica Tsai worries about her grandmother, Yun, who survived two wars in China before coming to the States, and whose memory has begun to fade. Though Yun rarely speaks of her past, Monica is determined to find Yun's long-lost cousin. Monica's discovery of a hidden family history is braided with Yun's own memories as she writes of her years in Shanghai, working at the Phoenix Pencil Company. As WWII rages outside their door, Yun and her cousin, Meng, learn of a special power the women in their family possess: the ability to Reforge a pencil's words. But when the government uncovers their secret, they are forced into a life of espionage, betraying other people's stories to survive.