What is the piano piece in the Infernal Serpent episode of Inspector Morse played by the Cheryl Campbell character?

Mozart Piano Sonata #11 in A Major, ('Alla Turca') K.331

Hi thanks for that but its not the peice i mean this is the specific peice she plays for Morse whilst he is looking through the family album and we can see the gardener outside who then runs in to tell her to stops you can see this right at the end of a section on YOU TUBE (I.M.The.Infernal.Serpent. Part 7.) enter the details in the bracket andgo to the last couple of minutes and se plays it ...this causes the gardener to come running in

As I said in my answer it is indeed parts from K.331 that are played while Morse is looking through the photo album. She starts with a fragment from the first movement theme. The score includes six variations on the theme but she jumps to the third variation. They double the first four measures before continuing to the octaves in the right hand which the actress could not probably play convincingly. There is no ambiguity about the answer. I have the score in front of me and a recording of the episode.

I managed to find this variation on YouTube, it is called Andante GraziOSo and the particular section is the third variation as the previous person has stated.