Angie Kim first stumbled upon hyperbaric oxygen therapy—HBOT—not as a novelist, but as a parent. One of her sons, then just a toddler, had been diagnosed with ulcerative colitis and also celiac disease, and the standard treatments weren’t helping, and an acquaintance mentioned that an HBOT facility just happened to be opening that summer in their Northern Virginia town.

Miracle Creek  opens with an explanation of how HBOT works. Patients are sealed into a submarine-like chamber, where the atmospheric pressure is adjusted to be significantly higher than normal, and then—wearing a helmet connected to an O2 tank outside—breathe in 100 percent oxygen. The idea is that damaged cells need oxygen to heal, and this allows the penetration of more oxygen, which is supposed to lead to better healing. It’s an FDA-approved treatment for burns and carbon monoxide poisoning. But it’s an experimental treatment for all kinds of things: autism, cerebral palsy, infertility, ulcerative colitis. Which means that, like a lot of other experimental treatments, people use it when they’re not sure what else to do. One potential hazard of the treatment: All that pure oxygen means there’s an elevated risk of fire.

In a way, it’s amazing that there aren’t more novels set in HBOT chambers: a disparate cast of characters, with complicated histories, trapped together on a regular basis, acutely aware of the unlikely possibility that something could go wrong. “It’s this weird crucible,” Kim says. “You go in there with three other families. You can’t get out because you’re sealed in, and you’re dependent on other people.” The kids watched DVDs, and—just like in the book—the parents talked. “It was a very intimate atmosphere,” she recalls. “We shared our life stories, we shared our plights with our kids.” In the chamber, she felt relatively lucky: other kids were up against a lot, she thought, and meanwhile hers was “doing pretty much fine.

“I was really forced to think about what does it mean to be happy? What does it mean to have challenges in your life?”

So when she went to start a novel more than a decade later, HBOT chamber was the obvious place to start. She’d never written a novel before—Kim started her career in litigation—but a fiction-writing book she’d read suggested that a good setting ought to be a kind of crucible, and here she had experienced exactly that first-hand. “I just thought, The HBOT chamber, it’s perfect.”

When the novel opens, the worst has already happened. The fire that killed two people—one parent and one child—is over, and the murder trial has already begun. The defendant is the child’s mother, who pushed too hard, who obsessed too much, who maybe just couldn’t take the stress of being the single parent of an autistic child. But of course, it is more complicated. Kim rotates between voices: Young Yoo and her husband Pak, the Korean immigrants who run the center, and their unhappy teenage daughter Mary; Matt Thompson, the lone adult patient in the chamber when it burned; Teresa Santiago, whose daughter survived; and Elizabeth Ward, whose son didn’t. But as the plot unravels, it becomes clear that guilt and innocence are concepts too big and messy to be contained within the narrow confines of the law.

Miracle Creek is Kim’s first novel, but in another sense, she’s been training for it all her life. Like Mary, Kim immigrated to Baltimore from Korea in middle school; like Young, her parents ran a grocery store downtown. It is a book about parenthood, yes, but it’s also, at its core, an immigration story. An immigration story, and a good old-fashioned legal drama. It’s not an accident Elizabeth’s trial propels the novel: Kim didn’t love being a lawyer, it turned out, but she loved—still loves—the theater of the courtroom, which is, itself, another kind of crucible.

But if the circumstances of the novel are extreme—a dead kid, a murder trial, a medical pseudo-submarine—the questions at its heart are about as fundamental as it gets. “The book is first and foremost about sacrifice for your family,” Kim says. “How far are you willing to go? How far does that sacrifice extend?”

Rachel Sugar is a writer living in New York.