Thomas Hudson takes the boys goggle-fishing near a sunken steamer. Joseph and Andrew are in charge of the dinghy while the others go diving. Thomas Hudson lets Tom and David have the first chance, with Roger along with them. Thomas Hudson goes below to the galley and talks with Eddy, who warns that the boys are scattering underwater. Thomas Hudson goes topside and relays Eddy’s warning to Roger. Eddy comes up and urges Thomas Hudson to stand guard with the rifle. Thomas Hudson moves the boat closer to the reef. Eddy goes back down below to finish fixing dinner.

Thomas Hudson relaxes, lying on the bridge to watch the boys. When he asks Eddy to bring him a drink, Thomas Hudson notices that he has Mercurochrome staining his lips. Eddy explains that he had “some sort of trouble” the night before but refuses to go into more detail about it.

Eddy spies a hammerhead shark approaching David. He and Thomas Hudson shoot but miss. They keep on shooting, but the shark continues to approach. Finally, Eddy hits the shark and it sinks. The boys crawl into the dinghy and come back to the boat, excited by the encounter. Roger is shaken and apologizes for letting the boys swim out too far. David regrets that they could not catch the shark.

The boys continue to discuss their dangerous encounter despite Roger’s extreme feelings of guilt. Both Thomas Hudson and Eddy tell him they were all responsible, not he alone. Joseph rows out to where the shark went down, but he can see nothing. The boys want to continue to goggle-fish at low tide, but Thomas Hudson is now nervous about the boys’ being in the water. David takes responsibility for going too far and tells his father he should not feel guilty.

Eddy reassures Thomas Hudson that it will be safe for the boys to fish at low tide. At dinner, when Eddy goes below to the galley, Andrew asks if he is a “rummy” (alcoholic). Thomas Hudson answers the question by pointing out how Eddy killed the shark. Rummies do not have that kind of accuracy. Andrew says he saw Eddie take eight drinks from a bottle. Young Tom and Thomas Hudson defend Eddy and his drinking. They then ignore Andrew’s comments and ask Eddy to have another drink with them. Eddy speaks with pride about shooting the shark, the alcohol clearly making him feel much better about the situation. Thomas Hudson sees this, worries, and volunteers to stay on the boat with him, but Eddy says he is all right and does not need someone to watch over him.