Toxoplasma gondii is the cause of the most common opportunistic infection of the brain in AIDS but is extremely rare as the cause of a solitary lesion of the spinal cord. Symptoms are weakness of the lower limbs followed closely by paralysis unless diagnosed and treated early. We present such a case in an intravenous drug abuser with AIDS and emphasize that MRI is the diagnostic tool of choice and that the index of suspicion should be high in immunosuppressed patients.