he shock hit Lindsay with a sharp stab of physical pain. "No," she whispered. "It can't be."

Sophie gripped her hand tightly as they read the short entry under Cordelia's name. The glowing green letters spelt out on the black screen,

Cordelia Brown. What a story! I'd love to see the look on Splash Gordon's face when she finds out the love of her life has feet of clay. I've made some enquiries, and her new book is out in December. And surprise surprise, it's called Ikhaya Lamaqhawe. Very African! How could Cordelia believe she'd get away with it? I'm going to have some real fun with this, once I've worked out the best way to use it. Thank goodness Anisha's letter got through.

"But what does it mean?" Sophie puzzled. "Okay, it connects Cordelia to Alison, but what on earth is it all about?"

Lindsay sat staring at the screen, as if willing the words to disappear. Eventually, she slowly said, "I guess we'd better find Anisha's letter." But she made no move to return to the boxes of papers.

Sophie got to her feet and put her arms round Lindsay. "Just because Alison thought she had something on Cordelia, it doesn't mean there's anything sinister in it. You said yourself that no one would ever believe Alex's evidence. So why are you placing so much importance on it? He probably saw Cordelia there on a completely separate occasion and just got confused."

Lindsay shook her head. "I don't know what to think, Sophie," she said dully. "A couple of hours ago, Cordelia said she'd never met Alison, and I saw no reason to doubt her. And now this! What am I supposed to make of it?"

"Lindsay, you can't draw any conclusions till you've read this mysterious letter from Anisha, whoever she is," Sophie urged. "Come on, I'll help you look."

Lindsay moved like an automaton towards the piles of papers and sat on the floor. Sophie joined her and together they started working through the remaining letters and files from Alison's boxes. It was Sophie who struck gold. She stared at a slim blue airmail envelope with a Zimbabwean postmark. The sender's name and address were written on the back in a neat, flowing script. "I've found Anisha's letter," Sophie said, handing it over to Lindsay.

With a cold feeling of impending disaster, Lindsay pulled out the contents of the envelope. There were several sheets of thin airmail paper covered in the same hand. Lindsay closed her eyes and sighed. "I don't know if I want to know what's in this," she murmured. "You know what I want to do? I want to burn it unread."

"You can't stop now, Lindsay. You have to know," Sophie said gently. "Do you want me to read it first?"

Lindsay opened her eyes and shook her head. "No. You're right. I do have to know." She unfolded the pages and started to read. As she continued, her hands began to tremble, and her eyes filled with tears. At the end, she dropped the letter to the floor, saying only, "Dear God."

Sophie picked up the scattered sheets. "May I?" she asked.

Lindsay nodded. "Go ahead," she said bitterly, getting to her feet. "I need a drink, Sophie." She stumbled from the room, leaving Sophie alone with the letter. Filled with a mixture of anticipation and anxiety, Sophie began to read.

The letter was dated September of the previous year, weeks before Alison's murder. "My dear Alison," it began.

I don't know whether you will remember me, but in August 1985 you interviewed me and three other South African women. We were on tour with a protest cabaret, and when we came to Glasgow, you came to see the show and talked to us afterwards. I am writing to you because of all the newspaper and magazine articles that were written about us, yours was the best. You painted an honest picture without being sentimental, and the memory I have of you is a journalist eager to tell the truth.

We need your help now. In all honesty, I do not know if you can help us, but I can think of no one else. Some time ago, Joshua Shabala, a good friend of mine disappeared. No one knew what had happened to him, but we all had our suspicions that he had been taken away by the secret police. As you will know, finding out information about the actions of officials in South Africa is virtually impossible if you are black, but his girlfriend, a young teacher in the townships called Mary Nkobo, determined that she would discover what had happened to Joshua.

Mary was a talented writer. She had already written a play for us to perform. She decided that she would write down the story of her search, which she did in all its details. She called her story Black Hope. After a few weeks, it became clear to her that Joshua had been murdered by the secret police in South Africa, and she wrote all she could find out about this, too.

But in our country, asking too many questions is a dangerous path to take, and Mary too was arrested. Her manuscript was smuggled out to Zimbabwe by the same friend who is taking this letter. Mary had left instructions that if anything was to happen to her, the manuscript should be sent to an English writer, Cordelia Brown. She chose this woman because she had enjoyed her work, and when she had written her a letter to express her admiration, this Cordelia Brown had written back a very encouraging letter to her. Mary felt she could trust her. Now Mary, too, has disappeared without trace, and we fear that she has been murdered by the police.

Now this Black Hope manuscript appears to have gone missing. We have written to Cordelia Brown several times, but we have had no reply. A white sympathiser in Johannesburg has tried to telephone, but all she ever gets is an answering machine, and her messages have not been returned. I am turning to you in the hope that you can help us trace Mary's book, for hers is a story that must be told to the world. She was very reluctant to show her work to anyone over here, for our protection, she said. But I had read a little of the book, and I know that its dramatic power and force will strike a blow against the white supremacists who keep my people in chains.

I know you lead a busy life, but I beg you to help us make sure that Mary and Joshua have not died in vain.

The rest of the letter consisted of instructions to Alison on how to make contact with Anisha and her friends to report any progress.

Sophie could hardly believe her eyes. She turned back to the first page and hastily read the letter again. Then she picked up her copy of Ikhaya Lamaqhawe. No wonder Cordelia had caught so authentically the flavour of life in South Africa, she thought bitterly. Hastily, she got to her feet and dashed out of the study. Lindsay would never need her more than she needed her now.

Sophie found Lindsay in the lounge, carefully sliding a glass into a paper bag. "What are you doing?" she asked, bemused by the seemingly bizarre behaviour.

"This is Cordelia's glass," Lindsay explained calmly. "Jim will need to compare her prints with the thumbprint on the glass in Alison's flat."

Sophie almost panicked at Lindsay's coolness. She had expected rage, hurt, tears, and recriminations. Not this studied calm. She struggled to find words that would give Lindsay the support she needed. "You think Alex was right?" she asked cautiously.

"Looks like it, doesn't it?" Lindsay said bitterly. "There's only one explanation for that letter, isn't there? Cordelia was so desperate to have another literary success that she stole a dead woman's work. She must have thought that she was the only person who knew about Mary Nkobo's manuscript. You've read Anisha's letter - Mary hadn't shown anything other than small excerpts to anyone over there. And when Cordelia found out that somehow Alison had uncovered her deception, she panicked." Lindsay let out a long, shuddering sigh. "I can't take it in, Sophie. Cordelia as Alison's killer? It had never even crossed my mind. I was so convinced it was either Claire or Ruth." She carefully put the bag down on the table, then threw herself down on the sofa.

Sophie crossed the room and joined her, but Lindsay shrugged out of her embrace. "Please, Sophie. Just leave me alone. I know it's daft, but I really don't want to be touched right now."

Sophie let her go immediately but stayed on the sofa next to her. "You couldn't be expected to guess," she tried. "There was no reason on earth why you should connect Cordelia to Alison's murder."

"No reason on earth except for her guilt, you mean?" Lindsay raged. "Jesus, doesn't everything just fall into place when you get the key to it? The entry in Alison's diary about the political hot potato, you remember? She was hoping for some originality between the sheets! No wonder Cordelia wanted to 'help' me investigate the murder! No wonder she wanted to get me into bed to distract me, then drag me back to London. And I stupidly thought she was doing it to protect Claire!"

"There was still no reason for you to suspect her," Sophie argued, desperately wanting to help Lindsay but not being certain how to do it.

"Of course I should! I was the one person who knew damn well that she hadn't written a word of that book when I left last May. The time scale was all wrong. I should have known there was something fishy going on. And if I hadn't run off to Italy in the first place, none of this could ever have happened." Lindsay's face was like stone, her eyes cold and dead, her voice dull and flat.

"You really can't take responsibility for everything," Sophie protested, trying to control the anger she felt towards Cordelia. "Anyway, you didn't give in to her attempts to distract you. You stuck with it."

"I wish now I hadn't," Lindsay retorted. "How do you think it feels to know that the woman I loved and lived with for three years is a plagiarist and a killer? Jesus, where did she think it was going to end? Did she really think that killing Alison was any kind of answer?"

"Like you said, she probably panicked. She didn't expect any doubts to surface about the book's authenticity, she didn't have her answers off pat. Besides, you've told me yourself how twisted and provocative Alison could be," Sophie replied.

"Don't make excuses for her, Sophie," Lindsay said angrily. "She killed someone just to protect her reputation. Alison might have been a complete shit, but that's no excuse for what Cordelia did." She got up and restlessly paced the floor. "Not to mention flushing Jackie's life down the toilet then climbing into bed with her girlfriend just to keep tabs on what was going on."

"What are you going to do about it?" Sophie asked.

"I'm going to finish the job that Claire paid me to do," Lindsay said. "My personal feelings don't enter into it. Tomorrow morning, I'm going to see Jim Carstairs with a print-out of that file, Anisha's letter, and a set of Cordelia's prints. Then I'm going to report to my employer that I have completed my assignment. Do you have a problem with that?" she asked belligerently.

Sophie shook her head. She was desperate now to break Lindsay's calm to force her to release the emotions that were tormenting her. She struggled to find the words that would do the trick. "No, I don't," she said emphatically. "And frankly, I don't give a shit what happens to Cordelia. But I do care very much about you. And I won't sit quietly by while you go through this pointless self-flagellation. You've done nothing wrong. Cordelia's the one who's done wrong. So stop blaming yourself. By all means, let out your feelings of hurt and anger and disappointment. But stop behaving like you're the one person in the universe who has to carry the can. Blame Cordelia as much as you like, but don't blame yourself."

Lindsay stopped pacing as Sophie's words hit home. Then, like an animal in pain, she let out a roar of anguish and fell to her knees, sobbing like a child. Sophie leapt up from the sofa and cradled Lindsay in her arms till exhaustion finally stilled her tears.

At last, Sophie said, "Let's go to bed, Lindsay. Today's gone on long enough."

Lindsay got to her feet and allowed herself to be led through to the bedroom, where Sophie quickly undressed her and put her to bed with a hot water bottle. Then she too climbed under the duvet and held Lindsay's cold, rigid body till sleep finally released her from her pain.

At nine the following morning, Lindsay was waiting in Jim Carstairs' secretary's office, the damning evidence in her hands. While she waited for him to arrive, she persuaded his secretary to let her make photocopies of Anisha's letter. When he bustled in looking harried with a briefcase and an armful of files, he gave Lindsay a friendly grin. "Come on through," he invited her.

She hovered nervously in front of his desk while he deposited his papers, then looked up at her. "Sit down then," he said. "It's all right. I'm not going to eat you. Though after yesterday evening's little farce, don't be surprised if Antonis Makaronas does."

"I'm sorry I wasted your time," Lindsay sighed. "I should just have brought Alex straight to you, and we could have taken it from there."

"I can't deny that would have been the more sensible course," Jim admitted. "But what's done is done. And you've uncovered some very significant material. I think in Alison Maxwell's diary alone we have the basis of an appeal."

Lindsay nodded miserably. "I've brought that with me. But I'm afraid I've got some more information for you. It should be enough to get Jackie a Queen's Pardon, never mind to win an appeal."

His eyebrows rose. "I hope it's a bit more convincing than that young lad last night. Bit of a blunder, that was, eh?"

"Not really, as it turns out." Lindsay handed over Anisha's letter and a print-out from Alison's computer file. She sat in silence while Jim Carstairs read the letter, looking more and more disturbed as he neared the end.

Lindsay deposited the paper bag on his desk, saying, "This is Cordelia's glass from last night. Maybe you can get the prints checked against the thumbprint that was found in Alison's flat."

He sat bolt upright in his chair and for the first time, Lindsay was aware of his acute intelligence as he stared fixedly at her. "Let me get this perfectly clear," he said slowly. "You are making an accusation against Cordelia Brown in the matter of Alison Maxwell's murder?"

Lindsay nodded. "That's right. As you've probably gathered, Cordelia and I used to be lovers. We lived together till May last year, when I had to leave the country for a while. At the point when I left, she hadn't written a word of Ikhaya Lamaqhawe. Yet that book was published in December. Even if her publishers had worked like hell to get it out, it can only have taken her eight weeks to write. Now that's a nonsense when you look at the quality of the book and the research it must have entailed."

Jim nodded encouragingly. "Go on," he urged.

"Looking at Anisha's letter, it appears that Cordelia stole this Mary Nkobo's manuscript and published it as hers. Oh, she probably made a few changes here and there, but I suspect that the bulk of it is Mary Nkobo's work. Unfortunately for everyone, Anisha chose the wrong woman. She only knew Alison Maxwell, the journalist. She had no way of knowing she was handing her information to a woman who preferred the pleasures of blackmail to getting a stunning exclusive in the paper. But the very qualities that made Alison such a good journalist also made her a serious threat as a blackmailer.

"Faced with Anisha's letter, Alison of course put two and two together. I suspect she was holding the threat of exposure over Cordelia, and in doing that, she signed her own death warrant. Cordelia was spending time in Glasgow then, supposedly looking for me. I would imagine it won't be too difficult to put her in the right place at the right time." She stopped abruptly.

"I see," he said pensively. "And it's your contention that the boy you produced last night actually did see Cordelia leaving the flat?"

"That's right. I know that on the surface he might not seem the most reliable of witnesses, but I think he's telling the truth. He had no reason to lie, and he was so accurate about his timings. The reason I met him was nothing whatsoever to do with the murder. It was he who volunteered the information to me, and he said spontaneously that it was just after six because he heard the radio news starting as he left his client's flat. I believe him, Jim, I really do," she said persuasively.

He nodded slowly, and sat silent for a moment, as if he were carefully weighing what she had said in some private balance. Then he said, "You've done a good job, Lindsay. It can't have been easy for you to come here with this evidence."

Lindsay said nothing of her temptation to destroy the letter, merely saying, "How soon will Jackie be in the clear?"

"I can't be certain," he replied. "But I'll be placing this new evidence in the hands of the Procurator Fiscal just as soon as I've had this fingerprint checked. Then it will simply be a matter of deciding what procedure to adopt. The Fiscal may decide at once to re-open the case. If he does, I'll immediately apply to the court for Jackie to be released on bail pending appeal, and I'll apply to the Secretary of State for a pardon. It could be days, it could be weeks. But either way, she'll soon be free again. And I know she'll never be able to thank you enough for what you've done."

Lindsay shrugged. "She might thank me. But there are others who won't. And I've got to face one of them right now."