The "Stop Pills That Kill Act" aims to enhance federal efforts against counterfeit pills containing fentanyl or methamphetamine , defining such substances as those falsely marketed under another product's identity. It amends the Controlled Substances Act to explicitly prohibit acts involving fentanyl, its analogues, or any counterfeit substance, thereby strengthening legal enforcement against these dangerous products. The bill mandates the Drug Enforcement Administration (DEA) to develop a comprehensive operation and response plan within 180 days. This plan must outline strategies for federal law enforcement investigations and seizures, increase education and prevention efforts tailored for youth, and audit existing public awareness campaigns to improve their impact. Additionally, the legislation requires the Attorney General to submit annual reports to Congress, detailing data on seized counterfeit fentanyl or methamphetamine substances, including their form, contents, seizure locations, and information on charges, convictions, and sentences related to their illicit distribution, alongside ongoing prevention measures.