No. 19 was Michael Crichton's Eaters of the Dead:
This was definitely way different than anything else I've read.
It's written as an ancient manuscript - an Arab who ends up traveling with - and battling with - a band of Vikings. Included are footnotes by the "interpreter", adding insight into the text. But it's all fake! I am amazed at the detail Crichton included in making up a world and then interpreting it from the ancient outsider and then modern perspectives.