Sienna Nealon has dedicated her life to keeping those with powers from breaking the law at will. After years of filling a prison for the powered called the Cube, a Supreme Court decision opens the floodgates and lets all of them out again. Now Sienna finds herself going from hunter to hunted as the US government turns a blind eye while the former inmates target her and her friends for death. With the attacks hitting closer and closer to home, will Sienna be able to fight back against the overwhelming odds before she – or someone she cares about – gets killed?

For months, Sienna Nealon has been targeted by enemies that have hounded her at every turn, destroyed her reputation, and finally, struck at those dearest to her. Operating from the shadows, this mysterious group has never dared to show their faces in their quest for revenge against her. Until now. After crossing the final line, now her enemies have left themselves exposed for the first time, and Sienna will stop at nothing to drag them out into the daylight. Because while this may be her enemies' first time playing for vengeance, it certainly isn't Sienna's...

“Guy Friday is a hemorrhoidal pain in my a-” Sienna Nealon doesn't need any complications. On the run from the law, trying to carve out as much of a life for herself as she can, the last thing she needs is the idiotic Guy Friday pounding on her door one night, wounded and begging for help. But helping people is part of who Sienna is, and soon she's embroiled in the fight against an assassin with the power to seemingly appear and disappear at will. Hunted all over the United States, Sienna must protect Friday as the two of them explore his past in order to reveal the unbelievable secret ...

When Kat Forrest is nearly killed in Los Angeles by a man with powers and a mysterious grudge, Sienna Nealon doesn't think twice before coming to save the day. But as the threat grows nearer, old tensions between Sienna and Kat rise to the surface, and caught in the middle is Scott Byerly, a former flame of both of them. Will Sienna be able to put aside her grievances and save Kat from her attacker – and possibly herself – in time?

What makes a hero? For years, Sienna Nealon has worked with the U.S. government to protect the world against other people with powers beyond those of a normal human. But after several clashes with the current administration, she finds herself with a new employer, an independent agency dedicated to helping stop threats to humanity. When a new hero and villain rise in New York City, Sienna can't help but get involved, even as the U.S. government sends its own response team, led by an old friend...and a new enemy. Soon, Sienna finds herself once more against the odds, against the government, ...