Well, the "baddie" I found interesting as they weren't just rehashing old plots or old enemies. Sometimes an element of mystery and intrigue helps with the suspense - but then I can see we view it slightly differently.

Yep but it did have a rather "WWII submarine movie" feel to it. The part where the ship starts sinking and flooding. Regarding the part where Toby gives that look to the camera, it was a good touch. After all it's making the episode remembered isn't it? Well especially since that usericon of it.