This article explores the conjunction of the detective genre and genomic discourse with specific reference to Arnaldur Indridason's novel Tainted Blood (2000), a text that explores the recent history of Iceland and the endeavour, on the part of the biotech DeCODE Genetics Inc., to compile a database of the nation's genealogical and genetic history. Via an analysis of the conjunction of eugenic and genomic discourses with specific reference to the modern history of Iceland, this article argues that the detective narrative Tainted Blood mediates a complex engagement with the personal, familial, and national consequences of the decision to map the Icelandic genome with regard to contemporary debates around identity, ethics, and the law in the light of emergent genetic technologies.