• In a 28-year-old man with bilateral acute retinal necrosis, a severe, bilateral panuveitis, necrotizing retinitis, and retinal vasculitis developed. Severe vitreous traction on atrophic retina resulted in bilateral giant retinal tears with an inoperable retinal detachment in the right eye. A retinal detachment developed in the left eye that was reattached after a pars plana vitrectomy and two scleral buckling procedures, but ultimately became inoperable. Large numbers of lymphocytes in the vitreous aspirate and depressed serum complement levels may indicate that an immune mechanism was involved in the necrotizing retinitis. We present the first electron microscopic evidence, to our knowledge, that preretinal membranes occurring in rhegmatogenous retinal detachment due to bilateral acute retinal necrosis arise from retinal pigment epithelium.