Everyone is in a slump at one point or another, but George Macallan had it particularly bad and for a long time. While waiting for better times, he lives poorly and performs in circuses, lonely and disenchanted. He is surprised by the visit of Allan Pinkerton, who is the founder of the first detective agency in the U.S., which gives his life a new twist. Pinkerton offers him a job to direct the Kansas City branch which is the most dangerous city in the country. There awaits new adventures, new friends, and old enemies.