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Background Malignant meningitis secondary to melanoma is a rare and challenging diagnosis, particularly when presenting as subarachnoid hemorrhage (SAH).Case Presentation An 83-year-old woman presented with a three-week history of new daily persistent headache, subtle cognitive changes were noted by her family. Her medical history included chest wall melanoma treated with lymph node resection, radiotherapy, and pembrolizumab in 2019.On examination, she was afebrile and normotensive, without meningism or focal neurological deficit. Initial imaging revealed multiple convexity SAH and cortical and subcortical hemorrhages with no leptomeningeal contrast enhancement. Initial lumbar puncture showed frank blood only, and CT angiography identified an aneurysm unrelated to the hemorrhages.Her clinical condition deteriorated with episodes of confusion, fluctuating alertness, and focal seizures. Repeat imaging demonstrate further cortical subarachnoid haemorrhage.A second cerebrospinal fluid analysis confirmed malignant melanoma cells, establishing the diagnosis of malignant meningitis secondary to melanoma.Conclusion This case underscores the diagnostic complexity of malignant meningitis with hemorrhagic presentations, often mimicking common neurological emergencies. Early recognition and a multidisciplinary approach are essential for managing such atypical cases effectively.jidhin.raj@nhs.net