Ten days before Christmas - Mosquito Creek, Montana buzzes with Yuletide activity. Along with the arrival of relatives and old friends, two strangers appear. One man claims to be a real estate developer. A second man claims to be a gourmet coffee executive. Both newcomers also claim they never met. However, twelve-year-old Hanna Gaikis witnesses two events that conflicts with their stories. Risking discovery and serious harm, Hanna and Stephen Anderlund [12] find enough proof to convince the rest of their team they have another mystery to solve. And, suddenly the amateur sleuths must race the clock to reveal the true reason the outsiders have come to their town isn't land or coffee, but the cargo of a secret train heading their way...