Freshly-minted night shift driver Vanessa partners up with veteran Nikki, who refuses to discuss anything to do with the dragon threat-even after they share their first shocking "Code 45" experience together. Determined to dig into the mystery, Vanessa enlists the help of her DJ roommate Pierre-Yves, and discovers not only his surprising ties to the "scatter" crisis sweeping the tunnels, but also a link to a dark secret about her own family's past.