Which Robert Galbraith novel introduced J.K. Rowling’s detective Cormoran Strike?

The Cuckoo's Calling introduced J.K. Rowling’s detective Cormoran Strike.

Published in 2013 under the name Robert Galbraith, the novel follows Strike as he investigates the death of model Lula Landry. The police have classified the death as a suicide, but Lula's brother doubts that conclusion and hires Strike to examine the circumstances.

Cormoran Strike is a former military investigator who works in London. Robin Ellacott, initially hired as his temporary secretary, becomes an important part of the investigative partnership. Their professional relationship continues throughout the series.

The book was initially received as the work of an unknown debut crime writer. Rowling's identity was disclosed after publication, and the news led to a dramatic increase in sales. The novel's authorship was therefore hidden at launch, but its place as the first Strike book is unambiguous.