The huge house in the Scottish Highlands was hidden under fifty years growth of vegetation. To anyone passing it was just an ancient ruin invaded by rampant weeds.

But I had a feeling that I had been here before. Wasn’t there a beautiful Chinese water garden here, brimming with waterlilies and rare fish? What about the house itself and all those interesting artefacts collected by its former owner?

When I pushed at a loose stone in the mossy wall, it crumbled to the ground. The next stone along also disintegrated with a small shove. Before long, I had cleared so much of the wall that I could see one of the ancient ponds, and it was teeming with koi carp.

Beyond the ponds I noticed a door that was built into an intact side of the old building. I negotiated my way across several linked pools to reach it. On the inside, everything in the house was in a good state of repair. From the layout of the rooms and their contents, I remembered that this was the home of a famous scientist, and that it had been open to the public in the 1970s.

Then, on a back stair, I came face to face with a woman in modest 1920s dress. This was the housekeeper, just one of several staff who still lived here in secret. I swore that I would never reveal anything about my visit, nor those who kept the supposedly abandoned house.