The focus of the investigation is the Mongols Motorcycle Club. They are mostly a California group. Like all clubs, I’m going to stay out of the debate whether they are just a club or something else.
William Queen an ATF agent, then known as Billy St. John, joins the club and becomes a full time member. He even rises to a chapter vice-president. The thrilling parts of the book is the ride through subterfuge, deception and avoiding woopies that almost expose him in his ride to a full-patch member.
The evidence gathering was enormous and before the tech world that we know now; iPhones, drones, National Security Agency info gathering, etc. Towards the end Queen as Billy, appears to have developed a close relationship with his "brothers." It feels like it’s hard for him to take them down. ATF and other law enforcement agencies descend on that fateful day and gather up more than 50 members on multiple charges.
I don't know why, I couldn't put this down.