Dr. Stone › Saison 1 Dr. Stone : Stone World

Chapter 15 — Episode 15

First, Gen leaves the village to avoid suspicion as an outsider, while the semi-final second match begins between Senku and Ginro. Ginro fights aggressively and recklessly after hearing that Ruri would accept any winner, dreaming of becoming village chief with ramen and a harem, but Senku defeats him using science-based tactics and advances to the finals. Exhausted, Chromu collapses after his own match, and Senku reveals he plans to intentionally lose the final so Chromu can win, marry Ruri, and become village chief. Then, the science team is woken up by Senku using ammonia smelling salts and immediately begins the 25-step process to synthesize the sulfa drug, starting from coal tar to extract aniline. Meanwhile, Gen discovers a water wheel built by Kaseki using river current to spin bamboo, which will power part of the production process. During the synthesis, Senku also produces carbonic acid, which Gen recognizes as the basis for cola, revealing Senku's deeper knowledge of modern chemistry. Finally, Ruri suddenly takes a severe turn for the worse after receiving an early dose of medicine, causing her condition to deteriorate rapidly. Senku diagnoses her illness as pneumonia caused by Streptococcus pneumoniae, and declares that sulfa drugs are specifically effective against this bacterium. After Kohaku passionately defends Senku and science before her skeptical father Kokuyou, the completed sulfa drug is administered to Ruri, who recovers and is able to run outside for the first time in years. At the end, a recovered Ruri shocks Senku by revealing she has always known his full name — Ishigami Senku — and Kokuyou declares Senku