Which J.K. Rowling novel was published under the Robert Galbraith name before her identity was revealed?

The J.K. Rowling novel published under the Robert Galbraith name before her identity was revealed was The Cuckoo’s Calling. It appeared in April 2013 as a crime novel featuring private investigator Cormoran Strike.

The story begins when model Lula Landry dies after falling from a London balcony. Strike investigates the death, assisted by Robin Ellacott, whose temporary office role develops into a central professional partnership. The book was initially reviewed as the debut of Robert Galbraith.

A Sunday Times investigation identified Rowling as the author several months after publication, and Rowling subsequently confirmed the connection. The revelation caused sales to rise sharply. The novel became the first entry in the Cormoran Strike series, while later installments were also published under the Galbraith name. The Casual Vacancy is the other major post-Potter novel associated directly with Rowling’s own name, so it is not the answer here.