Suspend your disbelief.

Basically, the whole plot of this film is highly improbable. Why is Deakin allowed the freedom of the train the whole movie? Whom does this benefit? Certainly not the conspirators, who suddenly have all sorts of unforseen problems the minute that he joins the party. After he points out that the Dr. has been murdered, surely they will lock him up. Nope, he still has the run of the train, meddling in every situation that arises. Even if they are too stupid to connect the dots between Deakin and things starting to go wrong, WHAT is their motivation for letting this guy roam around? If I was Fairchild, I'd have exiled him to one of the troop trailers and assigned several soldiers to be responsible for keeping him there. I enjoyued the film, but I have to suspend my disbelief, just like when I watch a sci-fi movie.