The Black Dudley Murder Author:Margery Allingham The Black Dudley dagger was shrouded in an age-old mystery. The legend said its blade would drip blood if touched by a murderer's hand. — It was an intriguing myth that thee guests in the old manor house decided to explore. The lights were turned out and the dagger passed from hand to hand until someone noticed it was covered with blood - and o... more »ne of the guests lay dying.
No one had seen or heard anything unusual - except Albert Campion. And only he knew they were up against the most diabolical criminal mind of the century.« less
Granted, this was Allingham's first Campion mystery, and supposedly they got better, but I found this to be boring and unreadable and gave up about 70 pages from the end. It's not a country-house mystery as one is led to believe, but an interminable trial of following a number of house guests trapped in the place with some criminals after a stolen something. Readers in 1929 didn't know Campion (not the main character here) was her prime detective, so they were led to believe he might be the culprit. Later readers know he isn't.
One other oddity I found was that the author misuses the word "infer" where she really meant "imply."