Cass Devane's life is turned upside down when her mother remarries and they go to live with her new stepfather and stepsister on Kwajalein, one of the Marshall Islands in the Pacific Ocean.

School is starting at Seaside High. Sixteen-year-old Cass Devane is nervous as she and her stepsister, Tabitha, ride their bikes to her new school. Will she get lots in the halls? Will people like her? Cass learns she has nothing to worry about. No less than four guys are vying for her attention. Whom will she date? Will all this attention drive a wedge between Cass and the tentative relationships she has with Tabitha, Logan, and her other new friends? As Cass plunges into her new school life, she soon realizes she needs help—fast! She knows she can rely on God, but who else will be there for her?

Sixteen-year-old Cass Devan and her stepsister, Tabitha, have settled into their year at school. Cass is dating Logan and Tabitha is dating Micah. But letters in the mail soon change everything. Tabitha receives letters from her mother, who has not been in contact with her since she deserted Tabitha when she was 4. Tabitha is torn between her allegiance to her father and the deep desire to know her mother better. Cass struggles to maintain a close friendship with Janette from Tennessee, but her friend just seems to be drifting away. What will she do? Both girls face hard decisions and family struggles as they look to God to lead them where He thinks best—and bring them safely home again.

When her boyfriend suddenly breaks up with her because of a mysterious family problem, Cass feels that he doesn't trust her.

Cass has trouble dealing with her mother's pregnancy, her "perfect" stepsister, and the absence of her boyfriend, who has left Kwajalein Island to attend college at West Point.

While Cass and her stepsister adjust to the new baby in their Kwajalein Island home, they face other situations which challenge them to rely on the grace of God.

On Kwajalein Island in the Pacific, bickering seventeen-year-old stepsisters Cass and Tabitha try to find God's way to help their friends Kira, who is under the spell of a violent and possessive boyfriend, and Rianne, who continues to struggle with anorexia.