Arriving home on Christmas Eve, Commander Gray Pierce discovers his house ransacked, his pregnant lover missing, and his best friend’s wife, Kat, unconscious on the kitchen floor. With no shred of evidence to follow, his one hope to find the woman he loves and his unborn child is Kat, the only witness to what happened. But the injured woman is in a semi-comatose state and cannot speak—until a brilliant neurologist offers a radical approach...

Off the coast of Brazil, a team of scientists discovers a horror like no other, an island where all life has been eradicated, consumed and possessed by a species beyond imagination. Before they can report their discovery, a mysterious agency attacks the group, killing them all, save one, an entomologist, an expert on venomous creatures.

The discovery of a burned body sprawled on a remote Australian beach shatters the vacation plans of Commander Gray Pierce. To thwart an ingenious enemy, he and Seichan are pulled into a centuries-old mystery surrounding a lost convict ship, the Trident.

To unravel a secret going back millennia, Director Crowe and Commander Grayson Pierce will be thrust to opposite sides of the globe. One will search for the truth, traveling from the plague-ridden streets of Cairo to a vast ancient tomb buried under the burning sands of the Sudan; the other will struggle to stop a mad genius locked within a remote Arctic engineering complex, risking the lives of all those he holds dear.

On a transatlantic flight, the two black sheep of Sigma Force—Seichan and Kowalski—must set aside their mutual dislike as a mysterious fiery force knocks their aircraft out of the sky. This unlikely duo must use every skill, weapon, and bit of ingenuity to survive a night on a remote volcanic island, where their only refuge is the haunted, bat-plagued grounds of a seemingly deserted resort. But something horrific awaits the two, something ...

In the remote mountains of Croatia, an archaeologist makes a strange discovery: a subterranean Catholic chapel, hidden for centuries, holds the bones of a Neanderthal woman. In the same cavern system, elaborate primitive paintings tell the story of an immense battle between tribes of Neanderthals and monstrous shadowy figures. Who is this mysterious enemy depicted in these ancient drawings and what do the paintings mean?

In the dead of night, a faceless enemy hacks into the Smithsonian Institution’s network of servers, but it is only the first strike masking a larger attack. To rescue a biologist trapped in the National Museum of Natural History and to discover the true intent behind an assault that grows bolder and bloodier by the minute, Sigma Force must unleash its most headstrong operative—Joe Kowalski…

A remote military research station sends out a frantic distress call, ending with a chilling final command: Kill us all! Personnel from the neighboring base rush in to discover everyone already dead-and not just the scientists, but every living thing for fifty square miles is annihilated: every animal, plant, and insect, even bacteria.

The crash of a U.S. military research satellite in the remote wilds of Mongolia triggers an explosive search for the valuable cargo it holds: a code-black physics project connected to the study of dark energy, the energy connected to the birth of our universe. But the last blurry image from the falling satellite captures a chilling sight: a frightening look into the future, a view of a smoldering eastern seaboard of the United States in utter ...

A yacht bearing a young American couple is attacked by Somali pirates, leading to bloodshed and the violent kidnapping of the pregnant woman on board. To aid in her rescue from the lawless and war-torn jungles of coastal Africa, Sigma Force enlists a unique search team: former Army Ranger Captain Tucker Wayne and his military war dog, Kane. But what appears to be a straightforward mission turns into a fiery ambush and betrayal-for this most-va...

Off the streets in the medieval heart of Budapest, Captain Tucker Wayne and his war dog, Kane, rescue a mysterious woman fleeing three armed men. The secret she holds will unlock a terrible treasure, one steeped in blood and treachery, tied to a crime going back to the fall of Nazi Germany and a heritage of suffering and pain that reaches out from the past to wreak havoc today.

Deep in the Rocky Mountains, a gruesome discovery–hundreds of mummified bodies–stirs international attention and fervent controversy. Despite doubts about the bodies’ origins, the local Native American Heritage Commission lays claim to the prehistoric remains, along with the strange artifacts found in the same cavern: gold plates inscribed with an unfathomable script.

Seichan is ripped out of the Sigma series for an adventure all her own—but can she survive? The beautiful and elusive assassin wakes in a hotel in Paris with a deadly electronic collar fastened to her throat.

Sigma Force confronts humankind’s greatest threat in an adventure that races from the Roman Coliseum to the icy peaks of Norway, from the ruins of medieval abbeys to the lost tombs of Celtic kings. The ultimate nightmare is locked within a talisman buried by a dead saint – an ancient artifact known as the Doomsday Key.

From ancient Greek temples to glittering mausoleums, from the slums of India to the toxic ruins of Russia, two men must race against time to solve a mystery that dates back to the first famous oracle of history – the Greek Oracle of Delphi.

Operatives of the shadowy covert organization Sigma Force, Dr. Lisa Cummings and Monk Kokkalis search for answers to the bizarre affliction aboard a cruise liner transformed into a makeshift hospital. But a sudden and savage attack by terrorist hijackers turns the mercy ship into a floating bio-weapons lab.

In the mountains of Nepal…in a remote monastery, Buddhist monks inexplicably turn to cannibalism and torture – while Painter Crowe, director of Sigma Force, begins to show signs of the same baffling, mind-destroying malady…and Lisa Cummings, a dedicated American doctor, becomes the target of a brutal, clandestine assassin.

The crime is inhumanly cruel with horrific consequences both unthinkable and inevitable. During a service at a cathedral in Cologne, Germany, a band of armed intruders dressed in monk’s robes unleashes a nightmare of blood and terror, ruthlessly gunning down worshipers and clergy alike. The killers haven’t come for the church’s gold and valuable artwork, but for a priceless treasure secreted within: the preserved bones of the Three M...

A freak explosion in the British museum in London ignites a perilous race for an earth-shaking power source buried deep beneath the sands of history. Painter Crowe is an agent for Sigma Force, a covert arm of the Defense Department tasked with keeping dangerous scientific discoveries out of enemy hands. When an ancient artifact points the way toward the legendary “Atlantis of the Sands,” Painter must travel across the world in search of th...