S.O.S. A call for help. But whose finger had written it in the dust? Magdalen’s or Charlotte’s? They had both stood there, he remembered, for a moment or two, before going out of the room. Whose hand had secretly dropped to the table and traced out those three letters?

The faces of the two girls came up before him. Magdalen’s, dark and aloof, and Charlotte’s, as he had seen it first, wide-eyed, startled, with an unfathomable something in her glance . . .

He went again to the door and opened it. The boom of Mr Dinsmead’s voice was no longer to be heard. The house was silent.

He thought to himself.

‘I can do nothing tonight. Tomorrow—well. We shall see.’

Cleveland woke early. He went down through the living-room, and out into the garden. The morning was fresh and beautiful after the rain. Someone else was up early, too. At the bottom of the garden, Charlotte was leaning on the fence staring out over the Downs. His pulse quickened a little as he went down to join her. All along he had been secretly convinced that it was Charlotte who had written the message. As he came up to her, she turned and wished him ‘Good morning’. Her eyes were direct and childlike, with no hint of a secret understanding in them.

‘A very good morning,’ said Mortimer, smiling. ‘The weather this morning is a contrast to last night.’

‘It is indeed.’

Mortimer broke off a twig from a tree near by. With it he began idly to draw on the smooth, sandy patch at his feet. He traced an S, then an O, then an S, watching the girl narrowly as he did so. But again he could detect no gleam of comprehension.

‘Do you know what these letters represent?’ he said abruptly.

Charlotte frowned a little. ‘Aren’t they what boats—liners—send out when they are in distress?’ she asked.

Mortimer nodded. ‘Someone wrote that on the table by my bed last night,’ he said quietly. ‘I thought perhaps you might have done so.’

She looked at him in wide-eyed astonishment.

‘I? Oh, no.’

He was wrong then. A sharp pang of disappointment shot through him. He had been so sure—so sure. It was not often that his intuitions led him astray.

‘You are quite certain?’ he persisted.

‘Oh, yes.’

They turned and went slowly together toward the house. Charlotte seemed preoccupied about something. She replied at random to the few observations he made. Suddenly she burst out in a low, hurried voice:

‘It—it’s odd your asking about those letters, S.O.S.; I didn’t write them, of course, but—I so easily might have done.’

He stopped and looked at her, and she went on quickly:

‘It sounds silly, I know, but I have been so frightened, so dreadfully frightened, and when you came in last night, it seemed like an—an answer to something.’

‘What are you frightened of?’ he asked quickly.

‘I don’t know.’

‘You don’t know.’

‘I think—it’s the house. Ever since we came here it has been growing and growing. Everyone seems different somehow. Father, Mother, and Magdalen, they all seem different.’