Travis Kast is a former high-ranking military official who after the death of his wife and daughter now lives a life of squalor in a housing complex known as the Tower. But when aliens invade his city and start bombing the Tower, he springs into action. Along with his neighbor and her son he must try to make it down thirty-five floors as aliens begin to overrun the apartment building. The confined spaces of the Tower turn it into an intense battleground that is rife with danger around every corner. Travis is in for the fight of his life as he tries to lead his neighbor and her young son to safety.