The story opens with Tom complaining that life lacks adventure. It's been a while since they returned from Siberia, and a fresh Adrenaline fix is needed to take the edge off sitting around and reading books about faraway places. Tom wants to "go off in the jungle, fight wild beasts and escape from wild savages, all in the name of good fun." Tom's cravings are solved by the appearance of one Sam Preston, the owner of a large circus, who needs a new attraction for his side show. He has been informed of a place in the jungles of South America where a race of giants live. Sam's show "must have such a creature," and Tom is offered a princely sum to go procure one or two. Coincidently, the fellow previously sent on this quest by Preston has gone missing. Tom is tasked with either bringing him home or giving his remains a proper burial. To add insult to other natural hazards, a competitor in a rival circus, sics a generic bad-guy on Tom. He is to try and foil the plan and beat Our Hero to the prize. This guy is so bad, he is a wolf in priest's clothing. You can probably guess the outcome, but you'll have to read the story to be sure.