"Trick or treat!" The cry echoed around the cul-de-sac where we lived. It was Hallowe'en, and it seemed that every child in the neighbourhood was out, begging for sweets.

"I don't think it's right," my wife said as she laid out the bowls of treats by the front door.

"Nonsense," I said. "It's a fine tradition. Sure, we used to have Hallowe'en parties back when I was young. They used to be great fun." I started to get into my costume.

"Yes, but they didn't involve doing anything like this."

"Really?" I said. "You do know that Hallowe'en is an old Irish festival? Samhain - right? - the time of year just after the last harvest. It marks the transition into winter." I fumbled at one of the buttons on my jacket. I really should have put on my gloves last, but I was excited at the thought of the night's festivities. "Could you give me a hand?"

My wife came over and helped me adjust my clothing. After a few minutes she stood back and gave me an appraising look. "Not bad. Have a look."

I checked my appearance in the mirror by the front door. It was possible to see the bulges beneath the mass of bandages. But, unless you knew about them, they just looked like part of the costume. "Perfect," I said, and took up my position.

"I still don't think you should do this."

"Look," I said, "it's trick or treat. It's all part of the bargain - and you know I like to revive old traditions." My wife opened her mouth to reply, but there was a hammering at the door and the sound of excited voices. I nudged her. "Showtime!"

We opened the door. There was a gaggle of children standing on the path, dressed in their Hallowe'en costumes. Most of them looked like they had bought their costumes in a supermarket, but there were a few who had obviously had theirs made at home - either by themselves or by loving parents. The boldest of the children - dressed in a pointed hat, black cloak and Pippy Longstocking socks - stepped forward, holding out a paper bag.

"Trick or treat!"

"Trick," I said.

The little witch looked at me. "You're meant to give us treats," she said indignantly as only a ten-year old could.

"And I'm going to give you a trick," I said. I reached into the pocket of my costume and pushed the plunger I had hidden there. The front of my costume exploded, sending fake blood and entrails flying out. There was a moment of silence, and then screams.

My wife and I watched the children run away. "I hope you can reload that thing," she said.