Old Guns, meet Young Guns. Try not to shoot each other.

Frank Cage and Martin Kelvin thought they'd be awarded medals and a lifetime of beer for coming out of retirement to fight the living nightmare known as the Hollow. Instead, they became fugitives from the Colonial Shield Federation when they discovered the truth: the Hollow were just scouts for the Halcerite Empire, a brutal alien species that worships warfare and exterminates other races—and humanity is in their crosshairs.

When Martin's infected and kidnapped by the enemy, Frank will do whatever it takes to get his old friend back—even if it means teaming up with a group of Halcerite defectors who've rejected genocide. As human colonies begin to vanish in emerald fire, Frank must assemble the galaxy's most dysfunctional response team: a squad of Young Guns who've never fought a real war and some eccentric aliens who believe Frank's a prophesized warrior destined for victory.

The universe just got a hell of a lot more complicated, and these Old Guns are getting too, well, old for this. But they're also too stubborn to go down without a fight . . .

The second installment of this epic military sci-fi saga continues the exciting collaboration between USA Today–bestselling author J.N. Chaney and New York Times–bestselling author Nicholas Sansbury Smith that's perfect for fans of Expeditionary Force and Undying Mercenaries.