Seneca Thomas is an agent with XCEL, a secret government task force charged with capturing the dangerous shapeshifters that have infiltrated New York City, passing for humans. Her Native American heritage gives her a special gift - the ability to see the shapeshifters for what they are. But when her partner is killed in the line of duty, Seneca finds herself teamed up with Max Dempsey - a shapeshifter. And when the pair discover a growing army of shifters gathering beneath the city, Seneca will have no choice but to trust the one man she shouldn't.