The Camel Club / David Baldacci.

It exists at the fringes of Washington, D.C., has no power, and consists solely of four eccentric and downtrodden members whom society has forgotten. Their simple goal is to find the "truth" behind their country's actions.

One man leads this aging, ragtag crew. He has no known past and has taken the name "Oliver Stone." Day and night, Stone and his friends study wild conspiracy theories, current events, and the machinations of government, hoping to discover some truth that will hold America's leaders accountable to its citizens. Yet never in Stone's wildest nightmares could he imagine the conspiracy the Camel Club is about to uncover...

After witnessing a shocking murder, the Club is slammed headfirst into a plot that threatens the very security of the nation, full of stunning twists, high-stakes intrigue, and global gamesmanship rocketing to the Oval Office and beyond. Soon the Club must join forces with veteran Secret Service agent Alex Ford, who becomes an unwilling participant in one of the most chilling spectacles to ever take place on American soil. It's an event that may well be the catalyst for the long-threatened Armageddon between two different worlds, and all that stands in the way of this apocalypse are five unexpected heroes.