At the end of the 19th century a newly wed English lady and her husband travel to Istanbul with the Orient Express. On the train some strange things happen but when they are in Istanbul just a few days they stumble upon a murdered harem girl who turns out to be the daughter of one of the English diplomats, the man who was also on the train.
All the famous sight are visited in the novel. Crossing the Bospurus, the lavish estates along the waterfront, Topkapi Palace, Aya Sofia, the Blue Mosque. And it is obvious the author studied Ottoman history well while doing research in town. (I once read a novel where the author mentioned the desert around the town and I was like WHAT???).
The mystery is not that plausible and I got a bit sick of the hints towards bedsport that was however never mentioned (seen) but this novel was still a good read because of the setting. I studied in Istanbul when I was young and this novel was bringing all the settings back in my mind's eye.
When you plan to go to Istanbul, have been there or are interested in Ottoman history this book is a good read. But as a novel no 1 of the series is a lot better (have not read the others yet).