The storage facility is the size of a football pitch, so it's unlikely the furry visitor will be caught anytime soon.
Eurovision can be wonderfully weird but surely a live mouse would be the quirkiest prop in its history. Art director Naejin Kim, responsible for staging at the contest, looks serious, then bursts out laughing.
"There is no room for mice," she says with a smile.
The storage facility is the film set for Willy Wonka and the Eurovision factory.
The sets here are for the 31 nations taking part, as well as for the headline acts. Performers during the week-long event include Rita Ora.
Naejin's team have been getting the sets ready for months. She says: "The problem we have is there are so many countries taking part and very little time between set changes.
"Everything needs to be wheeled out really fast and wheeled off again." The stage set-up time between performances is under a minute.
"That's when things can get damaged," she says.
Each country's delegates decided how they wanted their set to look.
It was then made here or flown over.
All the countries signed off the sets last week after watching the first dress rehearsal.
Esta historia es de la edición May 10, 2023 de Irish Daily Mirror.
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Esta historia es de la edición May 10, 2023 de Irish Daily Mirror.
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