After the death of their parents, seventeen year old Liv Larson and her younger brother are separated by the foster care system. Her grades slip, her friends drift away, and she gives up on her plans for college. The only thing that matters is keeping the promise to get back to her brother. After months of solitude and anti-social behavior, Liv's best friend Riley drags her to their high school's rooftop solar flare party. Despite the beautiful lights dancing in the sky, Liv finds herself captivated by Zander, a mysterious boy with a crooked smile. For a few hours, she allows herself to feel normal again. That is until what should have been a small flare erupts into a massive solar storm. Cut off from the rest of the world with no sign of rescue, fear and paranoia begin to take their toll on the group. Battle lines are drawn and their ranks are divided. Soon, those left behind must embark on a perilous journey to save one of their own...but, something sinister awaits them in the shadows and it's undeniably connected to Liv. Can she keep her promise to reunite with her brother? What are Liv and her friends willing to do to survive? Will their bravery and determination be enough to save them all from a rogue military unit, a terrifying virus, and the things that go bump in the night? Or was Icarus really the KILLSHOT?