Where Two Million Years Have Gone

200 Mannen no Arika (200万年の在処)

Kohaku takes Senku back to her village, where he meets guards Kinro and Ginro and a sorcerer named Chrome. Although Chrome's attempts at sorcery fail to prove himself superior, Senku becomes impressed with how far Chrome has come on his own and makes him his apprentice. Learning that Chrome became a sorcerer to help Kohaku's sickly sister, Ruri, Senku tells him about the world that existed 3,700 years ago and decides to help him develop an antibiotic to save Ruri.