Gawber rubbed his chin. ‘Well, where is she now, sir? She can’t have disappeared into thin air?’

‘No, she hasn’t. She’s really very close. She has discarded the blue dress, hat and trainers, and is now dressed in normal, everyday clothes, working in an office, factory or shop; driving a car, a truck or pushing a pram; looking after a husband, a family or whatever life she has made for herself.’

‘All right, sir, but what’s her motive?’

‘Money. She began to milk Alicia Prophet for all the money she could. And that’s quite a lot, but when the poor woman realized that that was what she was about, she turned off the tap and Lady B snapped. In the absence of any other information, that’s the motive.’

Gawber frowned and rubbed his chin. ‘Well, where do we go from here.’

‘Back to the beginning, where else? We need to go back and interview all the witnesses. Check through all the evidence, look at the murder in an entirely different light. This is the unusual case of the murderer who wanted to be recognized.’

Gawber shook his head. ‘But we don’t know who she is. It’s all very complicated. Maybe we’ll never find the murderer.’

‘Oh, we’ll find the murderer all right.’

‘If she gets away with it, it will go down as the perfect crime.’

Angel raised his head. His bottom lip jutted forward defiantly. ‘There is no such thing as the perfect crime!’

Angel reached the top step, held onto the banister rail and breathed heavily. Those three flights of stairs had played havoc with the calves of his legs. He stood there to catch his breath, remembering with satisfaction that even though he was breathing a bit heavily, he had given up smoking finally three years earlier. He looked across the landing at the door with the number 19 stuck on it: that was Margaret Gaston’s flat. He listened out for banging drums and raucous electronic racket, but all was quiet. He was approaching the door, when it opened unexpectedly. A man wearing a crumpled grey suit, light-coloured, open-necked shirt, grey hair and a broad smile came out. He closed the door quietly then turned round. When he saw Angel, he gasped, his eyes lit up and the smile vanished; he put a hand across his mouth and nose and dashed past him down the stairs. Angel didn’t recognize him but he knew when a man looked guilty. And that man looked very guilty. His eyes followed the little man until he disappeared round the bend in the staircase. He turned back and noticed a wicked smell of brandy, then, thoughtfully, he crossed the landing and knocked on the door; it was promptly opened by Margaret Gaston. She was smiling.

‘Forgotten something, Luke?’ she said quickly. ‘Oh.’

‘Hello.’

When she saw it was Angel, the smile left her. Her eyes flashed and her face flushed up scarlet. She quickly closed the door to an opening of ten inches or so.

Through the gap, Angel could see that the top half of her was cosily wrapped in a short, quilted housecoat, but her long legs were uncovered down to her feet, which were snugly enclosed in the rabbit skin slippers.

‘Oh, I … I thought it was … somebody else,’ she stammered, closing the door another inch or two.

Angel put his hand on the door to keep it open.

She maintained the pressure on her side to narrow the gap.

‘I need to ask you a few more questions, Margaret. It won’t take long.’

‘I’m afraid it’s not convenient just now.’

‘Why? Have you something in there you don’t want me to see?’

‘No. No,’ she said, trying to be nonchalant. ‘I was just going to … take a bath, that’s all.’

Angel applied more pressure on the door.

‘The bath can wait. It’ll only take five minutes.’

Her face hardened. ‘Have you got a warrant?’ she said sternly.

The question quite surprised him. His eyebrows shot up. ‘I don’t need a warrant just to talk to you, Margaret,’ he said applying more pressure on the door. ‘What are you afraid of?’

‘Nothing,’ she said quickly. ‘Nothing.’ She suddenly pulled the door open wide. She knew she couldn’t win. ‘I’m not properly dressed for visitors,’ she said. ‘That’s all.’

Angel smiled wryly. She wasn’t properly dressed last time he interviewed her. She didn’t object to his presence then, so what was different?

He glanced round the room to see what it was that she may not have wanted him to see. He saw a part bottle of Napoleon brandy and a glass on the sideboard. Underneath the bottle placed in the shape of a fan were three, ten pound notes.

She dashed over to the sideboard. He saw her pick up the notes, fold them and deftly stuff them into her bra. Then she quickly picked up the bottle and glass, turned round to face him, switched on a smile, rocked the bottle invitingly and said: ‘Drinkie?’

He shook his head.

‘Oh no. Of course. You’re on duty,’ she said tartly. ‘Well, sit down, Michael,’ she said. ‘Won’t be a second.’

She shuffled off in the slippers into the kitchen, deposited the bottle and glass and came out with a packet of Silk Cut and a disposable lighter. She glanced down at the cot as she passed it to the sofa to check that baby Carl was asleep, she smiled briefly, then flopped athletically onto the sofa stretching out her long legs.

‘I thought you might have brought my picture back,’ she said as she tore off the cellophane from around the packet.

‘Er, no. I hope you don’t mind. I’d like to keep it until the case is solved, if that’s all right. Your landlady doesn’t mind.’

‘Right,’ she said crisply.

Angel took out an envelope from his inside pocket and pretended to read it. He tried to marshal his thoughts.

She tapped out a cigarette and lit it. She blew out a big cloud of tobacco smoke. ‘Well, what is it you want to ask me?’ she said.

‘Who was that man?’ he said without looking up.

She thought a moment then said, ‘Nobody.’ Then she slapped down the lighter boldly and blew out another big cloud.

He continued to look down at the envelope. ‘How long have you known him?’

‘Who?’

‘Mr Nobody.’

‘Oh, him?’ There was another pause. ‘He came to check the gas oven and the boiler. Make sure it doesn’t give off CO², and gas us while we were asleep.’

‘He reeked of brandy,’ he sniffed. ‘So do you. Do you entertain all your visitors with brandy?’

‘We just got carried away,’ she said with a grin.

‘Brandy is expensive.’

‘So what? I didn’t buy it, Michael. He brought it.’

Angel shook his head. ‘He brought a bottle of brandy to check on your gas boiler?’

She took a drag on the cigarette and breathed out loudly. ‘All right, Michael. All right. So he didn’t call to check the bloody boiler, but he has absolutely nothing to do with the murder of Alicia Prophet. He’s just a sweet little man who visits me almost every Friday in his lunch hour. Now, I don’t want you investigating him and upsetting his job or his wife. If any of this leaks out you could wreck his marriage!’

‘How long has this been going on?’

‘About a year.’

He sighed and shook his head. ‘What’s his surname?’

‘I can’t tell you that!’ she exploded.

‘Well, I daresay we will be able to find him easily enough. There won’t be many Lukes working at the gas board.’

‘I don’t want your men climbing all over the bloody gas board offices, Michael. You’ll give him away as easy as wink. He’s a quiet, nervous little man. He relies on me to be discreet. It’s not fair.’

Angel sighed. ‘Look here, Margaret, life isn’t fair. You have to do the best you can. But if you don’t do anything wrong, you can tell the truth, the complete truth, can’t you?’

‘Yes. Yes,’ she said irritably. She didn’t like being lectured. ‘Now what were those questions you wanted to ask me?’

‘What’s his name?’

She shook her head.

Angel said: ‘If his only crime is being unfaithful to his wife, I tell you, Margaret, I am not a bit interested … probably won’t even need to check him out.’