In late September and early October 1982, the Chicago area experienced a cluster of sudden deaths that linked back to a common, ordinary product: Extra-Strength Tylenol capsules. Between September 29 and October 8, seven people—ranging in age from 12 to 35—died after ingesting Tylenol (acetaminophen) that had been deliberately contaminated with potassium cyanide. The incidents are widely considered the first well-documented instance in modern U.S. history of consumer goods on store shelves being tampered with to poison end users. Authorities initially treated the deaths as separate, unexplained cases. Only after toxicology reports identified cyanide in victims’ systems did the Chicago Police and the FBI recognize a pattern. Investigators traced the contaminated capsules to several Chicago-area pharmacies and grocery stores. Public alarm rose quickly as vasectomized products in sealed bottles—a product previously trusted and ubiquitous—were implicated. Johnson & Johnson, the maker of Tylenol, swiftly recalled approximately 31 million bottles of Tylenol products from pharmacies, hospitals and store shelves across the United States—an unprecedented nationwide recall at the time. The company also halted production and advertising, and later introduced tamper-resistant packaging, including glued boxes, foil seals, and plastic safety seals, which became industry standards. Retailers and manufacturers across many consumer product categories adopted similar measures. The case generated intense media coverage and prompted changes in law enforcement coordination, forensic toxicology, and product-safety regulation. The Federal Anti-Tampering Act of 1983 made it a federal offense to tamper with consumer products, increasing penalties and enabling federal jurisdiction for such crimes. The investigation itself involved law enforcement agencies at local and federal levels, but despite numerous leads and suspects—including a prominent early suspect whose charges were later dropped—no one has been convicted for the murders. In 2009, a man who had sent a letter claiming responsibility and who had worked briefly at a packaging plant was named a prime suspect by the FBI, but evidence was inconclusive and the case remains officially unsolved. Beyond the criminal investigation, the Tylenol case reshaped public expectations about product safety and corporate crisis response. Johnson & Johnson’s decision to issue a broad recall and communicate openly with the public is frequently cited in business and communications studies as a pivotal example of crisis management—though some critics at the time questioned aspects of the response. The industry-wide adoption of tamper-evident packaging markedly reduced similar incidents in the decades that followed. The 1982 Tylenol murders stand as a watershed moment in consumer-product history: a grim example of how a common over-the-counter medicine became a vector for deliberate harm, and a catalyst for regulatory, legal, manufacturing, and packaging reforms intended to protect consumers. While other historical incidents involved poisoning via food or drink, this case is distinct in its targeting of sealed, mass-distributed, brand-name consumer goods and in prompting systemic changes that persist today.