midnight
On this day , as it was his seventieth birthday , the Doctor had asked a few friends to share his mid-day meal , and when he returned from his morning stroll he sent for his housekeeper to give her a few final instructions . The housekeeper , who was a voluble Italian peasant-woman , after receiving his orders , handed him a piece of paper on which a few words were scrawled in reddish-brown ink , saying it had been left by a Signore . `` What Signore ? '' asked the Doctor , as he perused the document , which consisted of words in the German tongue to the effect that the writer regretted his absence from the Doctor 's feast , but would call at midnight . It was not signed . `` He was a Signore , like all Signores , '' said the housekeeper ; `` he just left the letter and went away . '' The Doctor was puzzled , and in spite of much cross-examination he was unable to extract anything more beyond the fact that he was a `` Signore . ''