The Girl In The Plain Brown Wrapper by John D. MacDonald

A Florida salvage consultant travels to a quiet Gulf Coast town to honor a dying woman’s last request: uncover what’s behind her daughter’s sudden mental collapse. What begins as a personal favor turns into a perilous probe of corrupt doctors, developers, and politicians who are drugging, exploiting, and silencing victims to protect their schemes. As he peels back layers of blackmail and violence, he fends off hired muscle, navigates fraught entanglements, helps the young woman reclaim her life, and delivers rough justice to the powerful men hiding behind respectable façades.

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