“But one of the most important rules of diving is if you don’t feel right, don’t go down.”

Key uses this line to provide a sense of foreboding about the dive. Although Mr. Sims wisely chooses to stay in the boat, Julie acknowledges that even outside of her father’s health, other conditions do not feel right either. However, Julie and her father let the prospect of making a much-needed sum of money from the dive cloud their better judgment.

“Even after hundreds of dives I still get nervous when I can no longer see the surface or what’s below me. I also get nervous as the sunlight is filtered away and the water grows colder. That’s when you know you’ve entered the danger zone: another world, an aquatic wilderness where humans are not meant to be.”

Julie’s description of the in-between space between the surface and ocean floor allows readers to visualize her experience, even if scuba diving is an unfamiliar activity. She also demonstrates her humility, showing that as a human, she knows she does not belong at the bottom of the ocean, and should take caution not to overstay her welcome.

“There’s a thing I heard all the time from dad about Mother Nature. She doesn’t mind you admiring her, but she lets you know if you’ve gotten too close and overstayed your welcome. And if she feels disrespected and finds you vulnerable, stripped of all your comforts and safety, she’ll throw challenges at you. She’ll make sure you don’t forget for a second who’s really in control.”

Julie’s father teaches her of nature’s power and the respect it deserves. Key chooses to personify nature, making it a character in the novel with which Julie must reckon. He highlights the Unyielding Force of Nature, reminding readers that humans are powerless against it.