Satan's Price. Book 3 of Operation Clean Slate (en Inglés) - Mark Kennedy

The Tolek fleet is inbound. Nine months to arrival. Nine kinetic impactors already launched - six at Earth, three at Mars. The species that sent them has not responded to any communication attempt except one, and that one is a secret Dren is keeping from almost everyone.

A Tolek dissident - the Elder - is offering a path to coexistence. The cost is a man Dren promised to protect. The alternative is extinction. Dren is running the math on both.

On Mars, Lieutenant Torres has been cleared to fly despite an injury that nearly ended her career. She and Jackson will take an untested gunship into the path of an impactor moving at seventeen hundred kilometers per second, alongside two other crews who trained for thirty days for a mission that allows no second attempt. On Earth, President Whitfield is holding together a coalition of nations that trust each other only slightly more than they trust the Tolek. And in the Belt, a stolen weapon prototype has changed the strategic calculus in ways no one fully controls.

The impactors will not wait for the politics to resolve. The fleet will not wait for the engineering to mature. The price of survival is being calculated in rooms across three worlds, and not everyone agrees on what the species can afford to pay.

Satan's Price is the third book in the Operation Clean Slate series - hard science fiction where the physics is real, the engineering matters, and the margin between survival and extinction is thinner than anyone wants to admit.