Glenn Crocker (Glenn) suffered a workplace injury that prompted Glenn’s doctor to prescribe drugs for pain relief. The drugs included Demerol (a narcotic) and a new drug developed by Winthrop Laboratories (Winthrop) (defendant) called talwin. Doctors were then unaware that talwin could cause addiction because Winthrop specifically marketed the drug as nonaddictive. Glenn became addicted to talwin, obtaining multiple prescriptions and making illegal purchases of the drug. Glenn then underwent a process of detoxification, which left him with a low tolerance for drugs. Glenn pressured his doctor into giving him an injection of Demerol, which resulted in Glenn’s death. Glenn’s wife, Clarissa Crocker (Clarissa) (plaintiff), brought suit against Winthrop for wrongful death and for Glenn’s suffering while he was alive. The evidence showed that talwin was a useful drug that had no addictive effects for a majority of its users but that Glenn was among a significant minority of patients who became addicted. The trial court found in favor of Clarissa. The appellate court reversed, reasoning that Winthrop could not have reasonably foreseen Glenn’s addiction. The Texas Supreme Court granted certiorari.