Bob's agrees to take Nugu, a distressed teenage boy, with him on a photography assignment into the dangerous Nagambo country because the boy's home is near his destination. On route Bob's safari meet a lone unarmed Swiss doctor, Dr Becker, who is searching for the secret of the miraculous boka drug (right). Becker becomes highly excited when he learns that Nugu knows all about boka. Nugu is injured by a charging rhino but Dr Becker revives him quickly with an injection of adreneline. When Becker's bag goes missing Sheena goes after Nugu and and learns he only wanted to learn the white man's magic that cured him (below). Nugu, Chim and the bearers mysteriously disappear overnight and Sheena, Bob and Becker are captured by Nagambo warriors. The Nagambo emperor wants to know where his son is but they are unable to answer. The emperor is about to execute them all when Nugu arrives and tells his father that Becker saved his life. The emperor and Becker exchange information about boka and western medicine and they are accepted by the Nagambos.