Unholy Crusade — Dennis Wheatley

With an effort Adam came back to earth. This was no dream but really happening. Adam Gordon, the poor Scots lad who, through a number of strange vicissitudes, had made good, become a best-selling author and flown out to Mexico in search of a background for a new book, had got himself caught up in a conspiracy to overthrow the government and, dressed in the costume of a Toltec Prince, was about to present himself as a Man-God to scores of credulous people. It was absurd, ridiculous-but a fact. Set in modern and ancient Mexico, Unholy Crusade recounts the adventures of 'Lucky' Adam Gordon, a young best-selling novelist who has gone to that country in search of background material for a new book, and who soon finds himself in love with the exquisitely beautiful but deeply religious Chela. Adam's ability to go back in time enables the reader to glimpse both the magnificent and barbaric sides of ancient Mexican civilisation, but this is only part of the story. Adam becomes entangled with a group of sinister individuals who are prepared to go to almost any lengths to achieve their evil ambition, finds himself continually fraught with danger, is caught between two powerful rival factions, and is forced to participate in blood-curdling pagan rites.