Has anyone tried putting Taylor Swift's piano in a bowl of rice ... and it just kept getting more and more rain," said Swift, 33, while seated at the piano for the show's surprise songs section.

"Pluie, rain," Taylor Swift exclaimed to the sold-out show inside ... Swift sat at the moss-covered piano and acknowledged ...

LONDON — Taylor Swift's moss-adorned piano encountered a hiccup Monday night ... we can officially declare it a rain show. Don't you? And rain shows are very, very special.