It’s rather a sticky business, and in any case I shall want the loan of your car. You’ll make a point of keeping the whole thing to yourself, won’t you?”

“Have you ever heard me going round blabbing out other people’s secrets?”

“Never,” admitted Sally. “That’s why I don’t mind letting you in on it.” She slid down into the chair, and leaning forward, helped herself to a cigarette from the box on the desk. “Sheila’s being blackmailed,” she announced bluntly, “blackmailed by that rotten twirp Granville Sutton.”

There was a brief pause.

“What’s she been up to?” demanded Ruth. “Having an affair with him?”

“Very much so, apparently. They were trailing about together a lot last autumn, and I told her at the time that I didn’t think much of her taste. It was no use talking to her then: she was absolutely besotted about him. He’s one of those plausible, good-looking crooks who can get round almost any girl if they choose to take the trouble.”

“I know.” Ruth nodded disgustedly. “The only thing that surprises me is that Sheila should be such as ass. I should have thought she was too keen on making a good marriage.”

“It was a sort of obsession: didn’t last very long. She had broken with him before she met Julian, and after that the only thing she wanted was to forget all about it.”

“And now I suppose he’s threatening to give her away?”

“He’s got a letter of hers.” Sally lit the cigarette which she had been holding in her hand and blew out a long trail of smoke. “I don’t know exactly what’s in it, but I gather that if it ever came into the wrong hands—” She shrugged expressively. “He’s offering to sell it back to her for a thousand pounds.”

“Is that all!”

“I told her she ought to go to the police, but of course she wouldn’t listen to me. Her one idea is to marry Julian, and if she had the money she’d stump up like a shot. As it is, the most she can raise is five hundred.”

“I see.” Ruth’s lips tightened. “And you’re to do the bargaining, I take it?”

“I’ve promised to go down and see the skunk. He’s got a bungalow at Playford, and the arrangement is that she’s to meet him there on Sunday night. He’s evidently afraid of a trap, and he’s not taking any chances.”

“So that’s why you want the car?”

“I had to say I’d take the job on: what else could I do? Sheila’s in a state of panic and she’d only make an unholy mess of it. I’m not the least frightened of the swine. I shall tell him that he can either bring the letter here next week and collect the five hundred or else he can hand it over to Julian and go to Hell. I’m absolutely certain it’s the right line to take—don’t you agree?”

“Speaking candidly, darling, I think you ought to be locked up.” Ruth surveyed her companion with a sort of exasperated affection. “You’re just about as hopeless as King Arthur and Don Quixote. Even if she is your sister, why the heck should you do all her dirty work for her? She’s quite old enough to look after herself, and the sooner she starts the better. It may teach her to behave more sensibly.”

“I’m only keeping a promise I made to Mummy.” Sally paused. “She simply adored Sheila, but she was always terrified that something would happen to her when she grew up. I was sitting by her bed holding her hand the evening before she died, and she suddenly told me in a whisper that it was the only thing she was really worried and unhappy about. I swore faithfully that if Sheila was ever in any trouble I would do my very best to help her. I know it comforted her, because she gave a little smile and I felt her squeeze my fingers. I couldn’t go back on that, Ruth—I couldn’t possibly.”

“My dear, I wouldn’t ask you to.” The elder girl nodded understandingly. “All the same, I’m not going to let you handle this job entirely by yourself.