Marianne de Pierres is an Australian author. Born in Western Australia, she has a BA in Film and Television and a Postgraduate Certificate of Arts in Writing, Editing and Publishing. She has been actively involved in promoting Speculative Fiction in Australia and is the co-founder of the Vision Writers Group, and ROR - wRiters On the Rise, a critiquing group for professional writers. She was also involved in the early planning stage of Clarion South. Marianne has published a variety of short fiction and is collaborating on a film project for Sydney-based Enchanter Films with New Zealand writer, Lynne Jamneck.
The greater body of her work has seen publication in the UK and Australia. In 2004, her series of novels with the protagonist Parrish Plessis, a postapocalyptic bodyguard and bounty hunter, was published in the United Kingdom through Orbit Books and in 2005 in the United States through Roc Books. The novels in this series include Nylon Angel, Code Noir, and Crash Deluxe and have been adapted into a role-playing game. Her second series, Sentients of Orion comprises four books: Dark Space, Chaos Space, Mirror Space and Transformation Space, published in the United Kingdom through Orbit Books. Dark Space was shortlisted for an Aurealis award and a Ditmar award.
In 2008 de Pierres began writing humorous crime under the pseudonym Marianne Delacourt.