Patient K.C. has been investigated by researchers for over 20 years after intracranial trauma from a motorcycle accident resulted in a unique profile of amnesia. K.C. suffered from severe anterograde amnesia, in both verbal and non-verbal domains. This was accompanied by a selective retrograde amnesia for personal events experienced prior to the time of his injury (episodic memory), with relative preservation of memory for personal and world facts (semantic memory). This pattern of spared and impaired memory extended to spatial memory for large-scale environments and beyond memory to future imagining and decision-making. MRI showed widespread changes including diffuse atrophy, left PCA infarct, and left anterior frontal encephalomalacia. Notably, there was severe atrophy of the bilateral hippocampi, parahippocampal gyri, left amygdala, mammillary body, and anterior thalamus (after adjusting for generalized atrophy). We present neuropathological autopsy findings and clinicopathologic correlations in a case that has contributed greatly to our understanding of mechanisms of memory, especially the distinction between episodic and semantic memory.