Edgar Wallace 
The Crimson Circle [EPUB ebook] 

The mysterious Crimson Circle is a high-level protection society: pay them, or you die. Every wealthy man goes in fear of them if he’s smart, and dies if he isn’t. This is a criminal genius who recruits people in trouble, rescues them with help or cash, and puts them to work on robbery, blackmail and murder. At least one man is dead after refusing to pay L100, 000. Will there be more bodies? The Circle has many minions, including the mysterious and beautiful Thalia Drummond, and many wealthy and high-powered potential victims. Derrick Yale and Inspector Parr track down the criminals in a race against time in this classic British detective thriller by the master of mystery Edgar Wallace.