I've enjoyed listening to The Leavenworth Case by Anna Katharine Green over the past week. Kirsten Ferreri reads it with a suitably "Victorian" overture for LibriVox, where it is available as a podcast download.

The Leavenworth Case was published in 1878, and is a nicely complicated murder mystery. The true culprit remains well veiled until a classic drawing-room climax. Apparently the book was praised for the mastery of legal points and was used at Yale University to demonstrate the fallacy of circumstantial evidence.