A series of mishaps in a reactor at the Three Mile Island (TMI) nuclear plant led to the 1979 meltdown of almost half the uranium fuel and uncontrolled releases of radiation into the air and surrounding Susquehanna River. It was the single worst disaster ever to befall the U.S. nuclear power industry. Health physics technician Randall Thompson's story about what he witnessed while monitoring radiation there after the incident is being publicly disclosed for the first time. It is supported by a growing body of evidence and it contradicts the U.S. government's contention that the TMI accident posed no threat to the public. Thompson and his wife, a nuclear health physicist who also worked at TMI in the disaster's wake, warn that the government's failure to acknowledge the full scope of the disaster is leading officials to underestimate the risks posed by a new generation of nuclear power plants.