Tommy could see in his mind’s eye Katie. Little slim Katie as she had looked when she played Puck. Never human, never of this earth.

‘The trouble is,’ he said, ‘it’s difficult to see Margaret in the role because we see someone else who was born to play the part.’

Sir John made a face. ‘It’s no good thinking of it, Tommy. Her Ladyship has made up her mind and I am not bringing the subject up again. But I’ll tell Miss Grey to put the girls on to study The Tempest and that will mean by the time I am ready to hear Margaret read the part, she will have some idea of what it is all about.’

Though it was not talked about, Miss Grey was nervous when she took the children out. She had, of course, never seen the orphanage Matron and only had Lavinia’s word for it that she was in London, but she could see that Margaret believed she was about, from the way she kept close to her side and kept glancing behind her. Because it was still the Christmas holiday Miss Grey had to take the girls out whenever it was fine, but she much preferred it when they amused themselves in the schoolroom.

What frightened her most was when they went to afternoon performances in a bus. They always drove both ways, but, when leaving a theatre, it was only too easy to get separated for a moment by the crowds.

Katie had not been told anything about Lavinia thinking she had seen the Matron. Much better not worry her, Miss Grey had decided. It is not as though she would be any help; if the Matron does make an attempt to kidnap Margaret there are enough of us to see she does not succeed. Then she comforted herself by feeling for her police whistle.

It was the police whistle which put Katie on to the fact that something odd was happening. Katie was nobody’s fool and very soon she had seen something was pinned under Miss Grey’s jacket. She was helped by the fact that every few minutes Miss Grey’s hand shot up to be sure it was still there. Katie would probably never have known it was a police whistle if, just as Miss Grey was giving it a furtive feel, Henry had not come in with elevenses on a silver tray. Miss Grey put her hand down so suddenly that the whistle caught on her little finger and, for a second, it was exposed to Katie’s view.

Katie said nothing but accepted the glass of milk and biscuits Henry handed her. But after he had gone she put her mind to the problem. She had never seen a police whistle, but she knew the police carried them. She had both seen and owned whistles, especially the sort that sang like song birds, particularly cuckoos. But what would Miss Grey be doing with a whistle?

That afternoon there was a matinée. It was a shocking day, raining cats and dogs and with a wind full of sleet. Lady Teaser was out playing cards and was not expected back until about six so Miss Grey – sorry for Katie cooped up in the house – let her go down and sit with Margaret while she got dressed for the play.