past perfect for the event that happened on the same day

Question

This is frustrating for me.

I read this sentence:

On Central Avenue they came to a small inexpensive hotel, the Atlantic House. As they had done at all the other hotels, they asked the clerk if they could see his registration book.They turned first to Friday, September 28, 1894, the day that Holmes, while already in possession of Alice, had picked up Nellie and Howard from their St. Louis home.

(The Devil in the White City: A Saga of Magic and Murder at the Fair that Changed America, by Erik Larson).

The detectives are trying to find this murderer who allegedly killed three children after taking them away from their mother, and the detectives are tracing him.

This past perfect use shows us that Holmes's picking up the children should have had some important relation to the past reference point.

It is possible to theorize that Holmes's action had relation to the detectives' turning first to Friday (by making the day that detectives turned to Friday the past reference point), but it seems too distant.

I think that the past reference point is the point at which Holmes signed in after picking the children up on the same day, but in the context, it is not yet revealed that Holmes actually checked in, even though by the nuance of it we can pretty much figure it out. Also, the past reference point is never mentioned directly,but only implied slightly.

Is it valid use of "had"? Is it fine to use past perfect with so slight an implication for the past reference point?

Answer 1

The reference date is Friday, September 28, 1894. The specific event on that day is what detective Geyer hopes to find out, namely, that Holmes checked into the hotel whose guest register the detectives are reading.

By using had picked up, we are meant to believe that something happened subsequent to (after) that action. The next sentence informs us

Geyer guessed Holmes and the children had reached Cincinnati later that same day.

Okay, so had reached refers to the same day, Friday, September 28, 1894. And later that same day tells us the had reached Cincinnati occurred after the had picked up in St Louis (or at least this is what Geyer guesses).

But this other instance of the past perfect leads us to believe that some action occurred after had reached Cincinnati.

And this action is the one that the scene is setting up for us: that Holmes checked into the hotel in Cincinnati.

It's a mystery: some suspense is built up in the reader by using these past perfects, but not telling us explicitly what action comes after them. But we can also follow the detectives' train of thought and we can guess that Geyer will find some clue to Holmes's checking in, which he does. (If not, we could hang the author for using language that deliberately leads us down a false trail.)

By the way, I read this book a year ago and recognized the excerpt. Great story–or I should say stories.