And Then There Was No One is a novel by Gilbert Adair first published in 2009. After The Act of Roger Murgatroyd and A Mysterious Affair of Style, it is the third book in the Evadne Mount trilogy. However, rather than being yet another more or less straightforward whodunit, albeit with postmodern overtones, And Then There Was No One thoroughly blurs the boundaries between reality and fiction; or rather, reality, fiction, and metafiction. As with the first two books in the trilogy, the title is again a variation on an Agatha Christie novel, And Then There Were None.