In the war on terror, the Executive, through the Central Intelligence Agency (CIA), has detained, mistreated, and tortured suspected “enemy combatants” in secret prisons around the world. Shocking evidence of torture and denial of due process has provoked widespread condemnation. Yet, the Executive continues to deny that its agencies-in particular the CIA-are prohibited by law from engaging in such activities. Scholars have argued that the Executive’s actions violate both international treaties and domestic statutes prohibiting torture. This Note takes a different approach and contends that, even in the absence of treaty or statutory law, the Constitution limits the authority of an executive agency like the CIA to act against foreigners abroad. The author relies on Supreme Court case law on the extraterritorial application of the Constitution, which holds that certain fundamental constitutional provisions limit the government’s actions wherever and against whomever it acts. She also highlights references to the fundamental rights approach in recent war on terror cases. She then argues that such fundamental rights include, at minimum, prohibitions against indefinite detention and torture under the Fifth Amendment Due Process and Self-Incrimination Clauses and the Eighth Amendment. Ultimately, she concludes that the Constitution simply does not permit the United States to engage in indefinite detention or torture-regardless of the end, the place, or the victim.