A young woman holds a secret document which cannot be released "That's the curious part about speaking the truth. No one does believe it." ; Agatha Christie, The Secret Adversary In Agatha Christie's second novel, The Secret Adversary, a young woman receives a draft treaty from a mysterious agent aboard the sinking RMS Lusitania in 1915. Four years later, two young adventurers are hired to find the woman and the treaty before the mysterious Mr. Brown can get his hands on the incriminating document. Xist Publishing is a digital-first publisher. Xist Publishing creates books for the touchscreen generation and is dedicated to helping everyone develop a lifetime love of reading, no matter what form it take.