Four years after the Perdido Beach dome went down, the alien virus that created it is still wreaking havoc, and virus-infested rock has created a new set of humans with mutant powers.

Rockborn Gang members Dekka, Shade, Cruz, Malik, Armo, and Francis are fresh off their defeat of Dillon Poe and in meed of answers to some very pressing questions: Who are the Dark Watchers? And what is this fourth dimension that only Francis can access?

But heroes don't get downtime. When the alien-virus-infested rock hits New York, a new foes, Bob Markovic, rises from the newly Rockborn. Markovic's arrogance and lack of a moral compass already made him unbearable. With his newfound power to inflict a deadly disease, he could send all humanity to a living hell. As the Rockborn Gang try to find their footing on morally gray grounds, they will have to make some tough decisions if they want to save the world.

Michael Grant bids farewell to the bestselling Gone universe with the finale to the Monster trilogy. Old friends and new foes come together in this battle for humanity. The mind-blowing and existential ending will make you rethink:

WHAT DOES IT TAKE TO BE A HERO?

This description comes from the publisher Hero is the third book in the Monster trilogy, the first of which is Monster; this is the sequel series to the Gone series, the first of which is Gone.