I learned that Langdon and his unnamed female accomplice are responsible for the deaths of an unspecified American family, in some unexplained way. And he is being pursued by the military of a vaguely southeast Asian country, at the request of two US diplomats who have no lines and are never mentioned again.
But this definitely happened in 1946, that much we know for sure... up until the opening credits. After that, who knows?
Also, you can totally be qualified to be a nurse in "wherever the hell this is" without knowing CPR.