The purpose of this article is to raise awareness to health professionals of a little reported complication of cataract surgery. To this aim we present a case report of a patient who developed an unusual post-operative phacoemulsification complication: retained intraocular metallic foreign body. A retrospective review of the patient's case notes was carried out and the findings presented. An extensive literature search to investigate the rate of occurrence of this adverse event showed that when the phacoemulsification technique was new, and now it is a widely established procedure, the problem of retained particles exists, and that metal fragments embedded in the iris following cataract surgery can be linked to surgical technique. The need for knowledge and vigilance regarding this unusual but significant complication by those seeing cataract surgery patients at the post-operative check, whether hospital ophthalmic staff or community optometrists, is highlighted and for the need of accurate reporting and recording of such incidents. The importance of contacting the relevant manufacturers and Department of Health agency of such complications as they occur is emphasized to ensure staff and patients have accurate and up to date information.