“I can prove that Sarah couldn’t have done it. I’ve got a witness who will swear to where Sarah was at the crucial time. You’ve had it, Cartwright. So listen to my proposition.”

His lips curled in a sneer. “You’re talking rubbish. But let’s hear this so-called proposition. If it’s blackmail you’re after, forget it. I haven’t got a bloody penny.”

“I got involved in this business because Paddy Callaghan was arrested. Since then, a lot of people have had a very shitty time because of you. I think it’s only fair that you should make it up to them in some small way. So all I’m asking is a written undertaking that you will withdraw from all negotiations concerning the purchase of Derbyshire House’s playing fields. When I get that, I’ll forget everything I ever knew about Lorna’s murder. Do we have a deal?”

He continued to pace back and forth. “If I pull out, which I might say is because of the way I feel about my Sarah’s death, what guarantee do I have that you’re not going to go around spreading these slanderous lies about me?”

“Why should I say anything? I’ll have got what I want.”

“And what’s to stop you coming back any time in the future and making more demands?”

“You’ll just have to take my word for that.”

His seemingly aimless striding around had brought him to within a few feet of Lindsay’s chair. Suddenly he lunged at her. Caught by surprise, she could only struggle feebly as his weight overturned the chair and pinned her to the floor. His hands were round her throat, squeezing. She could feel the bursting pressure in her chest as her lungs fought for air. Just as she felt her head start to swim, his hands came away as he jerked her to her feet and pulled his arm round her throat in a half-nelson. She gulped air desperately as he pulled her back so hard that her toes scrabbled to stay on the floor. With his free hand, he picked up a stiletto paper knife from the desktop. He held it to her temple and growled, “That’s what I think of your lousy proposition, Miss Gordon. Now I’m going to let go of your neck. And you’re not going to move a muscle. One move and this goes straight into your smart little brain. If you’re clear about that, say yes.”

Lindsay swallowed hard and croaked, “Yes,” through a dry throat. He let her go and moved surprisingly quickly round in front of her.

“Walk backward toward that other desk. One step at a time.”