Two papers that described a startlingly easy way to produce stem cells are apparently on the verge of retraction. In the face of new evidence that the data in the papers are incorrect, two remaining authors who had opposed the move have reportedly agreed to withdraw the work. The saga has raised anew perennial questions about the responsibility of senior authors on a paper and the efficacy of the peer-review process—although Science has learned that an initial paper on the stem cell method was rejected by Cell, Science, and Nature. Still, the work was ultimately published in Nature, leaving open a major question: How did leading stem cell scientists who were co-authors fail to detect the myriad apparent problems with the work?