Recent research on doctoral education in the U.K. has revealed the increasing number and diversity of academic relationships that shape the lives of research students, and students' own role in activating, mobilising and maintaining these relationships. Higher education policy reforms promoting doctoral "skills training", interdisciplinary communities, thematic centres and supervisory teams, all create new networks for students to negotiate. Often beneficial and supportive, this article explores the "unmentionable" consequences of relationships that gradually go awry. This study began as a project exploring the everyday experiences of doctoral students and early career researchers in the Social Sciences within the U.K. As the research unfolded, we began to encounter accounts of neglect, exploitation and denigration. While such stories have long been part of postgraduate life, their seeming persistence in the face of robust quality assurance and supervisory codes needs further exploration. We offer three portraits of difficult doctoral journeys to explore these "unmentionable" experiences and explore whether they are linked to growing institutional and career pressures on academics to prioritise research "productivity".