On weekends, the beautiful sound of cello music echoes throughout the corridors of Kyoto University's Center for iPS Cell Research and Application. It is played by Professor Koji Eto. He treasures the time of total serenity between his research. In 2018, Professor Eto succeeded in producing large quantities of high-quality platelets from iPS cells. His work was featured on the cover of a global scientific magazine, attracting much attention. What was the secret to his success? Professor Eto had discovered what researchers at the time had never thought of – megakaryocytes, the source of blood platelets, are "exposed to turbulence" to produce high-quality platelets. The clinical trial of iPS cell-derived platelet transfusion will soon begin at Kyoto University Hospital. It will be performed on patients with an intractable disease called thrombocytopenia, a condition of low platelet count. Meet Professor Eto and find out about his next challenge that can benefit the future.