The fate of Earth hangs by a thread— and Tessa Graham is the only one who can keep it from snapping.

As political tensions flare across the galaxy, a rogue faction known as the Human Defense League prepares to strike a fatal blow: the annihilation of Earth itself. Dr. Tessa Graham, Earth's weary guardian, must once again lead the charge to stop them. But this time, the threat is more insidious—reanimated mercenaries, ancient alien weapons, and a backlash that could doom the entire human race.

When the enigmatic Syfe twins offer Tessa a chance to travel back in time and prevent the catastrophe before it starts, she's forced to weigh the impossible: sacrifice the present to save the future... or let the spiral of destruction play out.

But the past holds more than just answers. It holds Devon—the man she lost, the life that could have been.

Torn between duty and longing, Tessa must navigate a web of loyalty, betrayal, and impossible choices before Earth's final clock runs out.