A scientist suddenly begins experiencing vivid displacements of perception: while physically present in familiar rooms he perceives himself on distant sunlit shores and aboard a schooner, and he becomes functionally blind despite retaining touch and hearing. Colleagues and friends try to rouse, examine, and care for him, testing explanations that range from somnambulism to neurological disturbance. The account traces their attempts to document and understand the episodes, probing the limits of sensory experience and the uneasy boundary between bodily presence and altered consciousness.