'But you're a very well educated man, sir!'

'Certainly so-and don't you forget it! And whilst we're on this education business, I just wonder, Lewis, exactly where Mrs. Purvis went to school when she was a girl.'

It seemed to Lewis the oddest question that had so far posed itself to his unpredictable chief, and the reason for it was still puzzling him as he brought the police car to a halt in front of the bollards that guarded Canal Reach.

Morse had known-even before he'd noticed the rows of paperback Catherine Cooksons and Georgette Heyers along the two shelves in the little sitting room.

'His name's Graymalkin,' Mrs. Purvis had replied, looking down lovingly at the grey-haired Persian that wove its feline figures-of-eight round her legs. 'It's from Macbeth, Inspector-by William Shakespeare, you know.'

'Oh yes?'

Lewis listened patiently whilst Mrs. Purvis was duly cosseted and encouraged, and it was a relief when Morse finally brought forward the heavier artillery.

'You know, you're making me forget what we called for, Mrs. Purvis. It's about Mr. Jackson, of course, and there are just a few little points to clear up-you know how it is? We're trying to find out a little bit more about the sort of odd jobs he was doing-just to check up on the sort of income he had. By the way, he was doing some work for you, wasn't he?'

'He'd finished. Rewiring the house, it was. He wasn't the neatest sort of man, but he always did a good job.'

'He'd finished, you say?'

'Yes-when would it be now?-'

'And you'd squared up with him?'

Mrs. Purvis leaned down to stroke Graymalkin, and Lewis thought that her eyes were suddenly evasive. 'I squared up with him, yes, before…'

'Mind telling me how much he charged?'

'Well, he wasn't a professional, you know.'

'How much, Mrs. Purvis?'

'£75.' (Why, wondered Lewis, did she make it sound like a guilty admission?)

'Very reasonable,' said Morse.

Mrs. Purvis was stroking the Persian again. 'Quite reasonable, yes.'

'Did he often do jobs for you?'

'Not really. One or two little things. He fixed up the lavatory-'

'Did you ever do any little jobs for him?'

Mrs. Purvis looked up with startled eyes. 'I don't quite see-'

'Mr. Jackson couldn't write very well, could he?'

'Write? I-I don't know really. Of course he hadn't had much education, I knew that, but-'

'You never wrote a letter for him?'

'No, Inspector, I didn't.'

'Not a single letter?'

'Never once in my life! I swear that on the Holy Bible.'

'There's nothing wrong in writing a letter for a neighbour, is there?'

'No, of course there isn't. It's just that I thought-'

'Did you ever read a letter for him, though?'

The effect of the question on the poor woman was instantaneous and devastating. The muscles round her mouth were quivering now as two or three times she opened her lips to speak. But no words came out.

'It's all right,' said Morse gently. 'I know all about it, you see, but I'd like to hear it from you, Mrs. Purvis.'

The truth came out then, reluctantly confessed but perfectly clear. The bill for rewiring the tiny property had been £100, but Jackson had been willing to reduce it by £25 if she was prepared to help him. All she'd got to do was to read a letter to him-and then to say nothing about it to anyone. That was all. And, of course, it was only after beginning to read it to him that she'd realised it must have been a letter that Ms. Scott had left on the kitchen table when she'd hanged herself. There had been four sheets of writing, she recalled that quite clearly, although Jackson had taken the letter from her after she'd read only about half of it. It was a sort of love letter, really (said Mrs. Purvis), but she couldn't remember much of the detail. It said that this man she was writing to was the only one she'd ever really loved and that whatever happened she wanted him to know that; and never to blame himself in any way. She said it was all her fault-not his, and…

But Mrs. Purvis could remember no more.

Morse had listened without interruption as the frightened woman exhausted her recollections. 'You didn't do anything else for him-anything else at all?'

'No, honestly I didn't. That was all. I swear on the-'

'You didn't even try to find a telephone number for him?' Morse had spoken evenly and calmly, but Mrs. Purvis broke down completely now. Between sobs Morse learned that she hadn't looked up a telephone number, but that Jackson had asked her how to get through to directory enquiries, and that she'd told him. It was only later, really, that she'd begun to realise what Mr. Jackson might be up to.

'You're not very well off, are you, my love?' said Morse gently, laying a comforting hand on the woman's shoulder. 'I can understand what you did, and we're going to forget all about it-aren't we, Lewis?'

Rather startled at being brought so late into the action, Lewis swallowed hard and made an indeterminate grunt that sounded vaguely corroborative.

'It's just that if you can remember anything-anything at all-about this man Ms. Scott was writing to-well, we'd be able to tie the whole thing up, wouldn't we?'

Mrs. Purvis nodded helplessly. 'Yes, I see that, but I can't-'

'Do you remember where he lived?'

'I'm sorry, but I didn't see the envelope.'

'Name? There must have been a name somewhere, surely? She must have written "Dear Somebody", or "My dear Somebody", or something? Please try to remember-'

'Oh dear!'

'It wasn't "Charles", was it?'

The light of redemption now beamed in Mrs. Purvis's eyes, as though her certain remembrance of things past had atoned at last for her earlier sins. '"My dearest Charles",' she said, slowly and quietly. 'That's what it was, Inspector: that's how she started the letter!'

Graymalkin's eyes watched the two detectives as they left-eyes that stared after them with indifferent intelligence: neither hostility against the intruders, nor compassion for the mistress. Now left in peace, the cat curled up on the armchair beside the fire, resting its head on its paws and closing its large, all-seeing eyes. It had been another interlude-no more.

That same evening Morse drove up to the J.R.2 in Headington, and spoke with the sister in the Intensive Care Unit. Silent-footed, they walked to the bed where Michael Murdoch lay asleep.

'I can't let you wake him,' whispered the sister.

Morse nodded and looked down at the boy, his head turbaned in layers of white bandaging. Picking up the chart from the foot of the bed, Morse nodded his ignorant head as his eyes followed the mountain-peaks of pulse-rate and temperature. The top of the chart read Murdoch, Michael; date of birth: the second of Octo- But Morse's eyes travelled no further, and his mind was many miles away.

The clues were almost all assembled now, although it was not until four hours and a bottle of Teacher's later that Morse finally solved the first of the two problems that the case of the Jericho killings had presented to him. To be more precise, it was at five minutes past midnight that he discovered the name of the man who had killed Ms. Anne Scott.