“Late. After we’d found Gordon in the distillery. There was a thumping sound like a door opening, and then footsteps.”

“You may be right about the killer being able to come and go secretly. I’ll have the team check to see if there are any clues to the secret walkways once I hear from the owners.”

“Well, it might also be a way to hide things. With the police searching the rooms…The thieves could be stuffing things in the walls.”

“There is that,” he said.

“But the main reason I wanted to come back here is something that just clicked in my brain.”

“What’s that?”

“Books travel easier than paintings and vases. Specifically, first editions. There are bound to be some here and in the library. They are transportable and can be hidden in luggage. Or, maybe they were looking for some reference to treasure in the house. The thing that is bothering me is how would they know about any of this?”

“Well, we already believe there is a third party who murdered the both of them. Perhaps that person stumbled onto something here. But again, why take advantage now?”

“Revenge,” I said. “That’s always a good motive. Maybe they had something against the O’Sullivans. I mean I like them both, but have they ever had trouble with the law?”

“No, they’re clean,” he said. “We checked into them first.”

“Oh.” I put my hands on my hips. There went that theory.

“Also, I keep saying, why draw attention to the negative side of things if it were the O’Sullivans. What has happened this weekend would only be detrimental to all of their hard work.”

“That is a good point,” he said. “Dead victims do not help sell tourist weekends.”

“Unless people are into true crime,” I added. “But I don’t think that’s what is happening here.”

“I agree.”

My brain felt like a ping-pong ball bouncing all over the place.

“It’s annoying that we only have twenty-four hours of the weekend left and still have so many questions,” I said.

“I couldn’t agree more. But shall we have a look around? While I don’t see criminals like them having much to do with books, that is just an assumption. We might as well check to see if you’re right about the first editions.”

The bookshelves covered most of the walls in the study. I hadn’t exaggerated about the wealth of books in this room. Along with first editions of Irish authors like Oscar Wilde,Jonathan Swift, and Bram Stoker, there were works by Jane Austen and other famous authors too.

“Everything is alphabetical, and there doesn’t seem to be anything missing,” I said after an hour or so of looking. “That said, there are several hundred thousand dollars’ worth of books on these shelves.”

He blew out a breath. “Blimey. Just for books?”

I nodded.

“So, if they were planning to take the books, they hadn’t done so yet.”

“Right. Though that could be a reach. I mean, most of the books he’d been looking at on the desk had been personal diaries. There is some correlation there, I’m just not sure what. Perhaps Carl was searching for inventory like I mentioned before. Either of the books, or whatever treasure we’ve heard about.”

I pursed my lips.

“What are you thinking?”

“One of the reasons the O’Sullivans have opened up the estate to visitors and have increased their whiskey production is to raise funds to help preserve the castle. I understand them not wanting to part with their treasures and family heirlooms, but just a few of those first editions could help cover their expenses for some time. I mean, there are a lot.

“And before you ask, no, I wouldn’t want to part with them if they were in my library, but I don’t own an estate that needs so much upkeep. Those books would help keep this place going for a long time.”

“But it wouldn’t stop the expenses from piling up,” he said. “They wanted to create a business that would help keep the estate running for many hundreds of years. Mrs. O’Sullivan mentioned that would be their legacy. That they would not rest on their laurels like their forefathers. Her words, not mine.”

“That makes sense,” I said. “They seem like very proud people. And they work hard. Look at how many of the classes and tours they do themselves. Okay. That explains why they wouldn’t want to sell off their prized possessions, but that doesn’t mean someone else wasn’t willing to do exactly that. Are you sure about the household staff? I know I asked before.”