She doesn't know who sent her, why they want it, or even what the heart of a planet looks like. But as the right hand and daughter of Thanos, and one of the galaxy's most legendary warriors, her job is not to ask questions. Her job is to do what she's told, no matter the cost.

What she doesn't know is that her sister Nebula is in hot pursuit. Nebula has followed Gamora to Torndune in hopes of claiming the planet's heart first and shaming her sister as vengeance for the part she played in Nebula losing her arm. While Gamora falls in with a group of miners attempting to overthrow the tyrannical mining corporation that controls their lives, Nebula allies herself with the Universal Church of Truth, whose missionaries wait on every street corner to recruit more followers and tithes for the Matriarch. Both sisters hope their alliance will give them access to one of the massive diggers capable of drilling to the center of the planet.

But the closer they get to the heart of the planet—and to each other—the closer they get to uncovering the truth of what brought them there and the role they may unknowingly be playing in a twisted competition with galactic consequences. A competition they can never win . . . unless they learn to trust each other.