Thinner by Stephen King

A successful but overweight lawyer finds his life spiraling out of control after a mysterious curse is placed upon him by a vengeful gypsy. As he rapidly loses weight, he becomes increasingly desperate to find a way to reverse the curse before it consumes him entirely. His journey into the dark world of curses and retribution leads him to confront his own guilt and the lengths he will go to save himself, culminating in a chilling and unexpected resolution.

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