The story

At L'Heure Bleue a cipher runs beneath the lyrics. When the midnight bell strikes, the tuner backstage goes down, and the next moment you are standing in front of the curtain again, one breath before the first line. Only one thing stays with you: every note you have just heard.

Montmartre in the 1920s. Singing on the stage of the cellar jazz club L'Heure Bleue, Madeleine learns that somebody's cipher is running underneath the songs she is being paid to sing. At midnight a single shot goes off, and Thibaut, the piano tuner backstage, goes down. Then the night rewinds to the first line of the evening. Madeleine has an ear that never forgets a note it has heard once, so in every rewound night she can keep count of how the flattened half steps, the footsteps and the silences have shifted a little from the night before. To stop the shot she has to read the cipher, and to read the cipher she has to take the hand of a man who will not say how many times he has lived this night already.

The night Thibaut sets the wrench down and says "So you're back again," and you find out you were not the only one carrying this rewind.
The moment your fingertips remember before your head does, the half-flat note that brushed past just before the last gunshot, and you put your hand exactly on the hollow under the third backstage stair.
The night you pull him off the piano and stand him out in front, and the bell strikes twelve and the shot follows him precisely to the place you moved him to.