BACKGROUND: We describe the re-emergence of a hidden residual intraocular silicone oil bubble after previous silicone oil removal. HISTORY AND SIGNS: A 57-year-old patient underwent vitrectomy with silicone oil for a complicated retinal detachment. Six weeks later silicone oil was removed via the pars plana and phakoemulsification with lens implantation was performed. Subsequent clinical follow-up showed an attached retina without residual silicone oil bubbles. However, more than 2 years later the patient suffered sudden visual loss. Clinical examination showed a bubble of silicone oil wedged between a remaining layer of anterior vitreous and the capsular bag, reducing central visual acuity. THERAPY AND OUTCOME: Complete extraction of the silicone oil bubble was performed via the pars plana. CONCLUSIONS: Residual silicone oil bubbles may wedge themselves into vitreous pockets in the ophthalmoscopically invisible regions of the pars plana. Over time these bubbles may migrate into the retrolental space with obstruction of the visual axis.