When a deadly and highly contagious virus appears, Doc Dee and Invisible Six must find its source. The mission takes them deep into the Rift, a lawless section of the Amazon rain forest. But bandits and wild animals are the least of I-6's worries when the true enemy is invisible, widespread, and can't be beat by typical combat. Can Doc Dee and I-6 locate patient zero and stop a pandemic from happening?

The US military is under cyberattack. Computer failures have crippled every weapons system. Gizmo and Invisible Six must discover who is behind this attack and the culprits' aim. But the mysterious hackers seem one step ahead of I-6 at every turn, and their use of autonomous weapons keeps I-6 from getting close. Can Gizmo and I-6 stop the worst cyberattack in US military history?

As a tropical cyclone churns across the Pacific, a cargo plane carrying nuclear weapons vanishes in the storm. Bicep and Invisible Six must recover the missiles before they fall into the wrong hands. Their mission takes them to a remote US military outpost in the Pacific. But the base soon comes under attack. Can Bicep and I-6 hold off an invasion long enough for backup to arrive?

Special operative Shade is working out of the US embassy in Tek City, Tekistan, when fighting erupts between rebel and Tek government troops. The Americans are trapped in this rebellion, unless Invisible Six can escort them to safety. But the Tek government wants to take the American civilians as bargaining chips. Can Shade and I-6 help the civilians escape from Chaos City?

Fighter pilots are performing routine landings on a US aircraft carrier when the impossible happens: the massive ship sinks in the South Pacific. Athena and Invisible Six are quickly deployed to the site to learn what happened and who is responsible. But the enemy is clever and soon makes I-6 look like the bad guy. Can Athena and I-6 unmask the enemy before another deadly attack occurs?

When a known terrorist attacks a US passenger jet, the CIA plans to retaliate with a drone strike. But Zumi proposes that they capture Viggo the Vulture alive to gain information on worldwide terrorist networks and weapons smuggling. The mission takes Invisible Six into the criminal underworld's darkest corners. Can Zumi and I-6 outsmart Viggo at his own game?