And then there was no one

The writer and professional controversialist Gustav Slavorigin is murdered in the small Swiss town of Meiringen during its annual Sherlock Holmes Festival, his body discovered with an arrow through the heart. With a price of ten million dollars on Slavorigin's head, almost none of the Festival's guests can be regarded as above suspicion. Except Evadne Mount, of course, the stubborn amateur sleuth and bestselling crime novelist from Gilbert Adair's The Act of Roger Murgatroyd and A Mysterious Affair of Style. Neither of those two cases, however, prepared her for the jaw-dropping twists of this new investigation, which climaxes at Meiringen's principal tourist attraction, the Reichenbach Falls - the site of Holmes's fatal confrontation with his nemesis, Moriarty.