Mermaid

Mexican-American lawyer turned P. I., Tom Aragon, investigates the disappearance of Cleo Jasper, a young woman who is as beautiful as she is simple-minded. Her doting brother will stop at nothing to find his defenseless sister, but Aragon realizes that he has once again found himself in over his head when Cleo's friend turns up dead amidst a sea of somewhat dubious suicide notes. Tom Aragon receives a strange visit at his law office: a 22-year-old woman named Cleo Jasper, self-described as mentally retarded, comes in to ask him about her rights.
The visit lasts fifteen minutes, then Cleo wanders off. Two days later, Tom Aragon is visited by a different Jasper: Cleo's older brother, Hilton, her legal guardian. Cleo has disappeared and Hilton Jasper wants to hire the lawyer to find her and bring her back. Has Cleo, a legal adult, taken stock of her "rights" and run away? Or did someone take advantage of the simple, suggestible young woman, and something more sinister is afoot? In this carefully-drawn character study, master of suspense Margaret Millar reveals hard and poignant truths about mental illness, the exploitability of those affected, and the challenges for their families, loved ones, and caretakers.