With the advent of recorded sound, the phrase found new form. Telegraph operators noted unusual sequences — breaks in transmission, ending with the rhythmic tap of a repeated phrase. Early recordings on wax cylinders captured faint, trembling voices uttering the words before dissolving into static.
Families preserved final phone calls from vanished relatives. Again and again, the last line held steady: "See you tomorrow." But something unsettled listeners. Over time, the voices changed. A son's call to his mother grew deeper each year, as though someone else was speaking through him.
A widow kept a voicemail that arrived hours after her husband's death in an accident. She replayed it for decades, though she admitted it no longer sounded like him. "It knows my name," she told a reporter, "but it isn't his mouth that says it."
Archivists who studied these voices often began to hear them outside the recordings. A tap at the window. A whisper behind the ear. The farewell repeated without source, as if the listener had been folded into the dialogue.
And always, it promised return: "See you tomorrow."