While out early in the morning, Allison and Wil witness Chief Conductor Welch getting pushed off the back of the train by a masked man. When Allison pursues, the man jumps on the roof and disappears after the train passes through a tunnel. Allison and Wil inform the other conductors and Ker about the situation, and they enlist help from Major Stork too. Gautier Terol, the wealthiest man on board, believes he is being targeted due to a death threat he received the previous day, and suggests he stays isolated from the other passengers for the time being...