Cry in Father's Bosom!! (Chichi no Mune no Naka de Nake!!- 父の胸の中でなけ!) - S1.E19

Zuuru held Gou in an island and tortured him to pry secrets of Voltes. Daijirou found a huge cave in the island and decided to investigate. He got caught and was thrown into a jail and met his father. When they tried to escape, Gou got caught again by Zuuru, but he managed to throw a piece of cloth with numbers written in blood to Daijirou.