Next week, in a little seaside town on the north coast of Australia called Tin Can Bay (population 1,900), a lady called Sharon Bates is going to get a lovely surprise.

Two people will be responsible for it, one she’s never heard of, and the other is me – and I wouldn’t even recognise her on the street.

But I did meet her once back in April when my mother and I dropped into the takeaway where she works to order some lunch.

Since then I’ve been carrying her name and address around on a piece of paper which was ripped from their order pad.

The surprise will be a parcel containing something Sharon’s wanted since she saw one about 10 years ago, and last week a man she’s never met bought it for her.

Cue flashback to the day in April when mum and I walked into the shop where Sharon works.

It was – as it always seems to be over there – a beautiful day. We had gone for a drive to see the town where mum had remembered holidaying as a child and, feeling hungry, randomly stopped at a little takeaway called the Snack Shack.

Mum was standing at the counter making conversation with the two ladies inside while I was sitting out in the sun waiting for our order.

Suddenly I heard the words “Oh my God, she’s got one of those Harrods bags...”

From here the usual conversation ensued about how I’d given it to mum, and as always mum managed to weave into the conversation that ‘her daughter lives in Oxford’ (you’d be amazed at how subtly mothers can weave in things like that).

Sharon, having had a thought pop in her head, blurted out “I don’t suppose if I put some money in your account you could...”

She then stopped herself and said “no, that would be silly, we’re complete strangers”.

Too right we are. How stupid would that be?

One of us could diddle the other out of the cash. So naturally I took her details and promised I would get her a bag when I was next in London.

That was now about five weeks ago and I was beginning to feel guilty I hadn’t managed to buy one for her. How bizarre, I don’t even know this lady!

Then out of nowhere last week, I phoned one of our listeners about a prize.

In passing, he mentioned he was standing in Harrods. Without thinking, I then blurted out “Don’t suppose you could do me a favour?”

I then explained the strange story, and about an hour later he phoned back to say that he was standing in front of the bags and “which one did I think she would like?”

All going well, this time next week Sharon won’t just have her new bag, she’ll also have a great story to go with it...