Suppose I tell you a story ?" Perhaps, there was some hidden meaning in this.

There was unquestionably a sudden alteration in his look and manner; the cook asked herself what it meant.
If she had seen the doctor at his secret work in the laboratory, the change in him might have put her on her guard.

He was now looking (experimentally) at the inferior creature seated before him in the chair, as he looked (experimentally) at the other inferior creatures stretched under him on the table.
His story began in the innocent, old-fashioned way.
"Once upon a time, there was a master and there was a maid.

We will call the master by the first letter of the alphabet--Mr.A.And we will call the maid by the second letter--Miss B." The cook drew a long breath of relief.

There _was_ a hidden meaning in the doctor's story.