Step two was where it invariably went wrong. I retrieved a long coat hanger made of thick wire, which I’d bent into a hook at one end and a handle at the other. I poked this rod through the gap and began fishing. What I wanted to catch was the pull rope that dangled inside. But I never did. After trying and trying, imagining the hook flailing aimlessly on the other side, I had to admit defeat once more.

On the seventh and final day of Zac’s absence I was twenty-seven-weeks pregnant and ready to try one last time with the garage. I thought about the fisherman who spent so long hunting a legendary beast he began to doubt it even existed, and that was when I finally hooked the pull rope.

I hardly drew breath as I slid the hook down the rope until it hit the knob at the rope’s end. Sweat dripped into my eyes but I didn’t dare break my grip to wipe it away. I climbed off the ladder, careful not to disturb the hanger’s position as I moved, then tugged it straight down. To my amazement, I could feel the lock release. I stepped aside, grabbed the handle, and shouted the word ‘Yeah!’ as the door lifted. I jumped up and down in triumph, forgetting for a second about my bump, then whispered, ‘Sorry, little baby.’

I left the garage door open to let in the April sunshine as I checked for cameras. I kept it open even after I discovered there were none. I needed light and air. I didn’t want that dark space to close in on me as I circled round it, taking a mental inventory of what was inside. Paint tins. A wooden work bench and tools. The carcasses of dead flies sprinkled across surfaces. If he had ever been in there, Zac would have shuddered at the dirt. In fact, that was exactly why this would be his perfect hiding place – anybody who knew him would discount it.

I lifted dust covers to see what was beneath them, tensing like a child who was frightened she would find a monster hiding inside, or a body. But all I found was an old bookcase with the wood splitting along one of the shelves, and an upholstered chair, covered in the obligatory ditsy fabric, with stuffing spilling out of the seat cushion.

There was nothing in there that could possibly belong to Zac. I rested my hands on the small of my back, tipped my head to stretch my neck, and closed my eyes. When I opened them, they were trained on a square shelf that hung from the centre of the garage ceiling, suspended by four short chains that were attached to each corner.