‘We’re going to pay a call on Armitage senior. According to the file, Bill’s home address is Queen Adelaide Court, just off the Mile End Road beyond Whitechapel. Being unmarried, his next of kin is a Mr Harold Armitage, his father. Retired soldier. Nothing so helpful as a search warrant in our pockets, Ralph, so we’ll just have to charm our way in. And while we go, I’ll fill you in on the latest developments in the Hive you discovered.’

‘What are we hoping to find chez Armitage, sir?’

‘Audrey’s handbag? The negatives? If Armitage is motivated by money he might have kept them back to do a little business on his own account. He claims to be motivated by patriotism but . . . I don’t know, Ralph . . . I think perhaps financial reward might play a starring role in all this. And let’s not lose sight of that necklace. No information from the usual sources?’

‘None, sir. Usual fences claim no knowledge. Could have gone abroad by now.’

‘Or been hidden until someone thinks we’ve taken our eye off the ball.’

‘But what’s the connection between Audrey and Armitage?’

‘She was prowling the corridors well before the murder – we only have her word that she saw nothing untoward. Did she catch sight of Armitage doing something questionable? Like letting himself into the Dame’s room with a pass key? She needed money in her changed circumstances and I think she was bold enough to attempt a spot of blackmail. She was certainly giving him a close inspection when we interviewed her down in Surrey. I put it down to the sergeant’s charming exterior but I think she very probably recognized him. She’d only have to ring up the Yard and leave a message. He would ring her back and arrange a meeting. The whole murder scene on the bridge has a professional ring to it. The rendezvous was set for exactly the time of poorest visibility. The witness, Arthur, said she turned to greet someone when the beat bobby approached. Wrong chap in fact but she could have been expecting to see a man in uniform.

‘Suppose, Ralph, our killer is waiting on the Embankment wearing, let’s say, a river policeman’s slicker and cap. No one would take any notice as their headquarters is right there by the bridge. They’re coming and going all the time. So he waits until the beat bobby has done his job and gone on his way then he approaches Audrey, grabs her bag and throws her over. Bag goes into the inner pocket of the cape and he strolls off unnoticed. I got taken for a policeman by a tram conductor myself, leaving Waterloo Bridge in a borrowed cape.’

‘Then perhaps I should be arresting you, sir? But, to answer my original question myself – we’re looking for a police cape possibly still stained with Group III blood and this item will have, secreted in an inner pocket, a lady’s bag containing photographic evidence of a dubious nature. If our luck holds, in the other pocket we’ll find an emerald necklace and a jemmy. And it will, no doubt, be hanging handily on the back of the door. With a confession pinned to the collar.’ Cottingham sighed.

‘Ralph, go home!’ said Joe on impulse. ‘I shouldn’t be involving you in this underhand operation. You’ve a wife and family to think about. I’m sorry! I was getting carried away. You’re right. I haven’t a clue what there may be to be found in Armitage’s house. He’s a careful type and has, of course, got rid of anything incriminating days ago. I just want to give it a try. Nosy, I suppose, but I wanted to get an impression of the man from his surroundings. He’s many-layered and I’m sure I don’t know all there is to know about Bill Armitage. Go back to the Yard. I’ll go on by myself. Constable! Stop here!’

‘Constable! Drive on!’ Major Cottingham of the Cold-stream’s authoritative voice countermanded Joe’s order.

‘Ralph, you’re not obliged –’

‘I know that. But I’m not happy about closing down this case any more than you are. It’s like looking at a suppurating wound and being ordered to slap a sticking plaster on it in the hope that it’ll go away. No, this calls for the scalpel and if I can help you wield it, I will. You said it, sir – “This isn’t bloody Russia!” We didn’t give our all in that hell for four years to emerge into an autocratic state where faceless men decide for us what the Law should be.’

They were dropped off at the City end of the Mile End Road and the driver assured them that if they struck out to their right they’d find what they were looking for. He didn’t risk taking his motor vehicle down into that warren – he was likely to emerge with bits missing and lucky if it was just the motor. He arranged to wait for them on the main highway.

They found the narrow entrance to Queen Adelaide Court. A grand-sounding title for a Victorian collection of slum dwellings erected for workers in the nearby docks. They stood, silently taking in the squalor and overcrowding of the terraced houses grouped around a central square. Joe spotted four outdoor lavatories and a central water pump. Washing lines crowded with drying linen filled most of the yard, reminding them that it was a Monday. Doors stood open on gloomy interiors; a few inhabitants were out on the doorsteps gossiping and casting an occasional eye on the bands of young children who played together in groups.

Springtime games were in full swing. Skipping ropes, whips and tops and hoops were being used by groups of girls, the inevitable football game, much circumscribed by the washing lines, raged around the perimeter. Once his initial shock at the noise and obvious poverty of the court had subsided, Joe noticed that all the children seemed happy and busy. A gang of small girls were first to challenge the strangers. Arm in arm, they were strolling along chattering and one was pushing a cart made from an old wooden fish box mounted on two perambulator wheels. It was lined with a dirty blanket and contained a selection of rag dolls. Joe bent to admire them as a friendly overture and was alarmed to see one of them move. The girls shrieked with laughter at his startled reaction.

‘’Sawright, mister! That’s just our Jimmy. ’E won’t bite yer! Not ’less you was to put yer finger in ’is marf!’

Joe explained that they were friends of Bill Armitage and were looking for his house.

‘Rozzers, are yer? That’s all right then. I’d took yer for gennlemen – watch chain an’ all,’ said the oldest with a sharp look at Cottingham’s waistcoat. ‘Well, come on then. ’Is dad’s in.’

Joe handed them a penny each and they set off, an unlikely cortège, to weave their way across the court, their every step followed by dozens of pairs of eyes.

‘I say, sir,’ said Cottingham quietly, ‘bit odd, all this, isn’t it?’

‘Bill’s a London lad. I expect he was born here.’

‘And that’s what’s odd. Remuneration’s not wonderful in the force, I’m sure we’d all agree, but he’s drawing a sergeant’s pay and he’s a single man. He could afford to live in the leafy suburbs like most of the CID blokes. Why’s he still here and what’s he doing with his salary?’

The girls led them to the open door of a house at the end of a row. It seemed larger than the others and the proud Victorian builder had, according to tradition, immortalized his wife or his eldest daughter by fixing her name over the door: ‘Violet Villa’.

‘Knock! Knock!’ sang out the girls in chorus. ‘Mr Armitage, you’re wanted! Visitors!’ They moved away in response to a raucous call from the other side of the court to come in for their dinner.

The doorstep was freshly donkey-stoned, the windows clean and the over-sized brass knocker gleamed. An elderly man appeared in the doorway. He peered out, failing to focus on either of them until Joe spoke. He had noticed that the old man’s eyes were both dimmed by the milky-white film of cataracts.

‘Sir!’ said Joe cheerfully. ‘Two visitors. I am Commander Sandilands and this is Inspector Cottingham. We are both colleagues of your son Bill and we’re all working on a case . . .’