Ah, General Zen. Our good ol' military, "Bluenose" twit. We don't know too much about him. All we know is what we saw of him in Munitions, plus maybe some clues we get from some cameos throughout the series. Also, no one has seen or heard from him since the Munitions Incident. The last we saw of him was at the very end of Munitions, when Sir Frederick Aura came to visit him before he was taken to the hospital... and he never made it to the hospital. For a long time, I've been under the assumption that Aura kidnapped him or killed him or something, but upon closer observation, I've realized there is MUCH more to this situation than that.
First of all, when Aura visited Zen, there was a doctor and several soldiers present. How on earth would Aura get away with anything there? Zen must have agreed to go with him. Going on a bit of a rabbit trail, when Aura kidnaps and murders Captain Grant two months after the Munitions Incident, Grant has no idea who he is. However, we know for a fact that Zen knew him based on this image from Paxton and Norman.
They seem to have worked together in the past, or had some sort of connection that Grant didn't know about. I'm gonna jump ahead here: in Swashbuckler, as The Thin Controller is leaving the hospital, a nurse tells Lola Lovefray that Zen never made it to the hospital. Going off of the fact that the doctor is one of Sodor's best (as stated in Culdee Fell), he probably didn't just lose a patient, especially an ex-general. He must have permitted Zen to leave, or is just really irresponsible and should be fired immediately. Assuming Grant's murder was after Zen went missing, Grant should have known that Zen had disappeared. Sure he resigned, but as a former captain, I'm sure he'd be well informed about the whereabouts of the general. Although, perhaps Grant was murdered BEFORE Zen went missing. However, I doubt it would have taken two months or more to get Zen to the hospital. Based on all this, Lovefray seems to be the only person who knows or cares that Zen is missing. At this point, I'm pretty boggled by this scenario. The only things I think I can say for sure is that Aura did not take Zen by force; Zen willingly left with him. Why? I have no idea. Maybe this was a business opportunity for him. Maybe now that he has been stripped of his rank and relieved of duty, he needs something from Aura. Maybe Aura owes him something. Maybe he did Aura a favor. Maybe he lent him The Military Jet for some of his dirty schemes. I don't know at this point. Matt, I can say with no doubt you have me stumped.
Well, just like last time, this "theory" consisted of a lot more questions than answers, so I for one am really looking forward to see what E's got for us.
After all this though, we know one thing: Sodor is 100% definitely governed by Time Baby!