Mum told me I wasn’t to speak to him and I never did.

“I bet he’s a spy. He’s been there three days in a row.” Jake knelt on the sofa and stared out of our living room window at the occupied bench by the lake. Jake was thirteen and reading John Le Carre.

“I bet a double agent betrayed him and now he can’t decipher the code he needs to move on to his next assignment,” he told me sagely.

From the back, the man didn’t look like a spy. He didn’t have a trenchcoat, or any sunglasses, just an old torn kagoul and a smudge of grime on his neck. I told Jake as much and he doused me with the full condescension of an older, worldly-wise sibling.

I started to feel a little sorry for the spy. I wondered why someone might betray him. He looked cold and I hadn’t seen him eat any lunch. It must be a demanding job.

The next morning the man was drinking coffee from a paper cup. I saw him trying to glance over the shoulder at the newspaper of the man sitting beside him on the bench. The man was giving him a wide berth and this gave me the start of an idea.

Mum came down and saw me staring. She frowned and sat down beside me on the sofa.

“Lucy, you know this isn’t like a story in a book don’t you?”

I didn’t answer.

“These people -” she hesitated. “They can be dangerous. You’re not to talk to him, do you understand? He’ll be gone in a day or two I expect.”

She did that thing with her mouth that showed she didn’t like the idea of something - like when the people selling the Big Issue asked if she’d like a copy. I nodded and mum left.

Lunch was tuna sandwiches, which I hated. No one noticed when I slipped one under the table and into a carrier bag I’d brought specially.

When we finished eating, Dad disappeared into his shed and I slipped into his study and grabbed his copy of the Telegraph. Obviously it wouldn’t do as it was, so I hurried up to my room and carefully cut out two round eye holes about half way down. Perfect.

I wasn’t allowed to boil the kettle so I ran the hot tap in the kitchen until it was as hot as I could make it, stirred three teaspoons of dried coffee into a dark soup in a mug, and, when I was sure no one was looking, I slipped out of our front door, across the road into the park.

Looking back, I don’t know what that man must have thought. He took the mug more out of surprise than acceptance. Then I showed him the carefully adapted newspaper that would save his bacon and handed him the soggy half sandwich wrapped in a Waitrose carrier bag. I kept my promise and never spoke one word to him, but tapped my nose, winked, and hurried away, confident that I’d just salvaged his operation single handedly.

I was right. The next day the spy was gone. Dad never worked out what had happened to his paper.