After a U.S. military research satellite crashes and a package containing artifacts linked to Genghis Khan is received at the Vatican, Commander Gray Pierce and his Sigma team must solve a mystery linked to Christianity's origins and a weapon hidden for centuries that holds the fate of humanity.

When a British archaeologist who had been missing for two years reappears, frantic and delirious, but dies before he can tell his story, Sigma Force must stop an ancient plague with ties to some of history's most innovative minds.

Wrongfully fired from their counterterrorist unit, operator Pike Logan and his partner investigate the disappearance of an exchange student while Taskforce teams are threatened by terrorists to cease operations at the risk of high-profile hostages.

As Syria's government unravels and ISIS emerges, planning to unleash a sarin gas attack across the entire Middle East, Crocker and the rest of SEAL Team Six must race against time to stop a ruthless killer and keep an explosive plan from detonating.

The Taskforce is used to being the hunter, but this time they're the hunted. Intent on embroiling the US in a quagmire that will sap its economy and drain its legitimacy, Russia passes a potential weapon of mass destruction to an extreme Islamic sect in Nigeria. A relic of the Cold War, the Russian FSB believes the weapon has deteriorated and is no longer effective, but they are wrong. Trying to solve the riddle of who might be stalking them, Pike...

Pike Logan is forced to choose between his administration loyalties and a vengeance-seeking friend who has gone rogue in the aftermath of a soldier's death during an operation being performed by a covert anti-terrorism taskforce.

Compiles real-life accounts of covert military operations from the past 50 years, from raids into Laos to U.S. Navy SEAL operations, highlighting the units that conduct clandestine operations around the world.

Thomas Crocker and his team of Navy SEALs head to Mexico after a U.S. Senator's wife and teenage daughter are kidnapped by the Jackal, a ruthless drug lord.

Sigma Force Commander Gray Pierce makes paradigm-shifting discoveries about human evolution while investigating shadowy figures depicted in Neanderthal cave paintings.

Putting aside his personal needs to join the Norwegian resistance during World War II, engineer Kurt Nordstrum makes a daring escape to England to transmit secret evidence of the Nazis' progress towards building an atomic bomb.