Douglas Bainbridge is an agent with the ONI.
At 25 years of age, this blond haired handsome man hailing from apparently the upper crust of San Franciscan society did not have to join the military as he enjoys a nice inheritance from his grandmother. He chose to serve out of a conviction that it was the right thing to do even though his parents clearly saw things differently. Having reached the quarter century mark, he is free to use his money as he saw fit without their annoying habit of trying (unsuccessfully) to use it to control his decisions.
We encounter him in the first recorded adventure as the cruise liner he is sailing on pulls into Shanghai harbor and he stands near the railing on the First Class deck, having paid the difference from Second Class out of his own pocket. He is excited for his new posting and ready to immediately meet with his new boss as soon as he was able to disembark. He is also surprised to learn that his impressive knowledge of both Mandarin and Cantonese will not do as well for him as he thought since the prevailing language in the city is its own Shanghainese. Being gifted in languages, though, he quickly picks it up.
Bainbridge holds the rank of Lt. Commander in the Navy and has been transferred to the Far East from his previous duty in D.C. as part of the Office of Naval Intelligence's immersion program and his first order is to take that to heart by traveling all about the city, especially outside the International Settlement, so he can learn what is really happening in that city of 3 million people, as of 1935, the year of his arrival.
Bainbridge is single with no interest in changing that as his mind is largely on his new assignment, this despite being the focus of many widows on the ship as well as older women wanting him to meet their marriage-age daughters. One in particular became especially close but when they landed, he was back to mostly all business.
The adventures we have of Bainbridge's activities all take place in the changing political landscape of that huge Chinese metropolis which will see its governance changing from British and French control, which is very irksome to the native populace, to that of the invading Japanese, which is hated to a huge degree. He will also find his work move from one of an observer reporting back home what he saw and heard to taking a lot more part in the things.