An unlicensed practitioner performing subcutaneous injections of large volumes of corn oil caused the death of one of her clients and life-threatening neurologic complications of a second client from systemic fat embolism. Several additional clients also came forward to report other serious complications they had suffered from similar procedures. The clinicopathologic and investigative findings from these cases are described. In both instances of fat embolization, the diagnosis was overlooked by hospital staff because of insufficient or misleading clinical history. The local and systemic pathologic manifestations of corn oil injections in 1 victim who died several days later from multiple organ failure are described. The clinical history and course of another who survived after 8 days of hospitalization are also presented. Similarities with complications from other forms of cosmetic oil injections are discussed. Laboratory analyses applied to confirm the nature of the injected oil and the course of criminal prosecution are also described.