The correspondence between the radical Venetian pro-female polemicist and nun Arcangela Tarabotti (1604–52) and the Copernican French astronomer Ismaël Boulliau (1605–94) — here published for the first time — shows how one of Tarabotti's most controversial works made it to press. She had long and unsuccessfully sought in Italy and in France to print the work, which was, puzzlingly, published two years after her death in Holland. It was subsequently placed on the Index of Forbidden Books. Charting the explosive work's journey to France and its later arrival and reception in Holland, the Tarabotti-Boulliau correspondence provides a case study in the circulation of unorthodox ideas in seventeenth-century Europe. By showing Tarabotti's firm inscription in the well-connected scientist's intellectual circle, the letter exchange furthermore contributes to our expanding notions of women's participation in the Republic of Letters, while also suggesting a confluence of radical scientific and social views.