Sara Ackerman grew up on Oahu, graduated from Punahou School, and then studied journalism and psychology in college. After earning a master’s degree in psychology, she got a job as a teacher and student counselor at Kahuku High School.

Ackerman might still be teaching and counseling high school students, but when acupuncture therapy restored her dog’s ability to walk she went back to school and earned a degree in Chinese medicine. (Though she is licensed, she is not actively practicing.) She also discovered that she enjoyed writing novels.

While the Big Island resident’s first three novels remain unpublished, the fourth, “Island of Sweet Pies and Soldiers,” a story of a tight-knit group of women living on the Big Island in 1944, was published in 2018. Her fifth, “The Lieutenant’s Nurse,” a love story set on Oahu in the last months of 1941, reached booksellers early last year.

Ackerman, 53, finished her newest novel, “Red Sky Over Hawaii” (Mira Press, $17.99; ackermanbooks.com), earlier this year. It’s the story of Lana Hitchcock, who leaves her crumbling marriage in Honolulu to visit her estranged father in Hilo.

But Lana’s father dies before she gets there and then the Japanese attack Pearl Harbor. Once she arrives on Big Island, the FBI start arresting “persons of interest” — including some of her father’s friends and neighbors. Unforeseen circumstances make her the unofficial guardian of two German American girls, a Japanese American fisherman and his adopted son. With FBI agents and an unsavory Realtor closing in, Lana takes them to the hidden refuge her father had secretly been building higher up on Kilauea — just in case Japan attacked the United States and the Imperial Japanese Army landed on the Big Island.

“Red Sky Over Hawaii” will be officially released on Tuesday.

Everybody in Hawaii knows that Japanese Americans were sent to internment camps for no reason other than their ancestry, and that some of them were held in camps here in Hawaii. The fact that Hawaii-resident German Americans were also imprisoned here doesn’t get the same publicity. How did you learn about it?

I learned about it from a co-worker. Her friend’s mother was one of the (German American) girls whose parents had been taken away.

Did anyone on the Big Island really build a hideaway like the one in the book?

Yes, Herbert Shipman, in 1941 in case of a Japanese invasion. I came upon that house when I was hiking and it’s a really cool house architecturally. That’s where I got the idea for that, so that’s based on a true story. My father was an architect, and had just passed away when I was writing it, so I pulled from that too.

What’s next for you?

I finished my next one, “Radar Girls,” in May. It’s about the Women’s Air Raid Defense (civilian organization) in Hawaii during the war. It’s based a little more in a real-life situation (than “Red Sky”). My agent is also my editor, so we’re editing it now. It will probably be out by the end of 2021.

How did you keep writing after you’d written three novels that didn’t sell?

I had a Post-it on my wall that said, “Patience and Perseverance.” You have to keep writing in order to be a good writer.

What do you enjoy doing when you’re not writing?

I teach a novel-writing class at HPA (Hawai‘i Preparatory Academy) — which is really fun — and English. I spend a lot of time on a stand-up paddleboard or swimming — or hiking. I go to the volcano as much as I can. I’m kind of a nature girl.