Lost voices trilogy

1.

3.7 stars

Fourteen-year-old Luce has had a tough life, but she reaches the depths of despair when she is assaulted and left on the cliffs outside of a grim, gray Alaskan fishing village. She expects to die when she tumbles into the icy waves below, but instead undergoes an astonishing transformation and becomes a mermaid. A tribe of mermaids finds Luce and welcomes her in—all of them, like her, lost girls who surrendered their humanity in the darkest

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3.

5 stars

When humans declare war on mermaids, Luce swims to San Francisco Bay where she finds a group of "twice lost" girls, lost once when trauma turned them into mermaids and again when they defied mermaid law, and unites them into an army under her leadership.