This case is one of a male patient in his mid-60s with a prior diagnosis of polymyalgia rheumatica and suspected seronegative rheumatoid-type polyarthritis who presented with 15 months of progressive generalized musculoskeletal pain, morning stiffness, fatigue, cognitive dysfunction, and non-restorative sleep. Repeated laboratory investigations, including inflammatory markers and an extensive rheumatologic work-up, were normal. Physical examination demonstrated no synovitis or objective inflammatory findings. Administration of the 2016 American College of Rheumatology (ACR) fibromyalgia criteria yielded a score of 22, meeting the diagnostic threshold.