The knitted jubilee topper has delighted residents since it was cable-tied to the top of the postbox outside the Bilton branch - but yesterday it went missing.
Post Office manager Amjad Ali said: “When I came to the branch at 9am the topper is the first thing I normally see.
“And yesterday it wasn’t there. I was quite disappointed, because it’s something that has been making a lot of people happy.
"When it was first put up it went viral on social media, and people say it’s been a focal point for the community.”
Ali first wondered if it might have been a completely random act, possibly by passing teenagers.
“But it was held on with very strong cable ties – and someone had cut clean through them," he said.
"So it looks like someone came with a pair of scissors specifically to do that.”
That morning Ali put out a post on Facebook, urging whoever took the topper to do the right thing and return it.
Scores of Rugbeians left supportive comments, and echoed the appeal for the topper to be returned.
And then came the news that a resident had found the topper lying in the street, almost half a mile away.
Ali said: "I had a message from a resident yesterday evening to say that his mother had found it on her way from work, and she
would be bringing it back tomorrow morning."
And the Good Samaritan was true to her word, bringing it back this morning - with Ali promptly restoring the topper to its rightful place on the postbox.
"People are delighted that it's back," Ali said.
"We've had people coming from all over Rugby to take pictures and to come into the branch to say how happy they are.
"I've had loads of messages of support as well.
"I still can't understand what would make someone want to take that topper and just dump it in the street - there are some bad
"But mostly, we've got a brilliant community, and we all stick together."