At the height of the roaring 1920s, the ex-frontier town of Denver, Colorado, emerged from the postwar boom as the future of the American city. But the slick façade of progress and opportunity masked a murky stew of organized crime, elaborate swindles, and widespread government corruption. Rookie district attorney Phillip Van Cise was already making national headlines for a new brand of law enforcement. Employing military intelligence tools he'd developed during the Great War, Van Cise crippled the criminal empire of Lou Blonger, an ex-lawman who had risen from petty scam artist to master of the Big Con. But Van Cise had even darker, more malevolent forces on his radar. The Ku Klux Klan had emerged as a shockingly mainstream middle-class movement, all while claiming to protect true American values. Utilizing his pioneering surveillance techniques, Van Cise was determined to expose the Invisible Empire from within. Gripping and exhaustively researched, this prescient chronicle of Phillip Van Cise's spectacular career as a feared gangbuster taking on organized crime, the KKK, and corruption at the highest levels of government is a cautionary tale that mirrors our tumultuous times.