Delilah Dirk is back for another adventure. She and Selim meet the Dutchman while in Turkey. He convinces Delilah to let him come along on their adventures as they search for the mythical Third Pillar of Hercules. The Dutchman, Laurens von Hassel, is also a journalist and records Delilah's adventures. Of course he then publishes the stories in his newspaper. Delilah Dirk becomes even more notorious then she already is. 

The Third Pillar of Hercules turns out to be a fascinating underground city in the Strait of Gibraltar. Selim is of course fascinated by the inscriptions in the temples they have discovered along the way. Delilah is a bit disappointed in the lack of treasure. And we are not completely sure what motivates the Dutchman. This book has a bit more depth than Delilah's other adventures. There is a bit less swashbuckling and a bit more archaeology and politics. That didn't make it any less enjoyable however.