J.K. Rowling is back with a new novel.

Publisher Little, Brown said on Monday it was publishing a second book by Robert Galbraith, the Harry Potter author’s thriller-writing pseudonym.

The Silkworm sees the return of detective Cormoran Strike, the ex-soldier hero introduced in The Cuckoo’s Calling.

Cuckoo initially attracted little notice when published last year but rocketed up the charts once Rowling was exposed as its author.

A lawyer has been fined for letting slip her identity.

The Silkworm will be published in June.