I thanked him all the same for his trouble, and he asked me to let him know, if I found out, who had taken his box.

Kate and I drove off towards the sea.

She said, 'Not a very productive bit of sleuthing, do you think? Anyone in the world could have borrowed the horse-box.'

'It must have been someone who knew it was there,' I pointed out. 'I expect it was because it was so available that they got the idea of using it at all. If they hadn't known it would be easy to borrow, they'd have delivered their message some other way.

'Well, never mind,' said Kate lightheartedly. 'Perhaps it's just as well Farmer Lawson had nothing to do with it. It would have been rather shattering if he had turned out to be the head of the gang.

I laughed. 'If I'd thought he could have possibly been the leader of the gang I wouldn't have taken you there.'

She glanced at me. 'You be careful,' she said, 'or you'll grow into a cosseting old dear like Uncle George. He's never let Aunt Deb within arm's length of discomfort, let alone danger. I think that's why she's so out of touch with modern life.'

'You don't think danger should be avoided, then?' I asked.

'Of course not. I mean, if there's something you've got to do, then to hell with the danger.'

She drove eastwards along the coast road and came at length to the long promenade at Brighton. Kate turned deftly into a square in the town, and stopped the car.

'Let's go down by the sea,' she said. 'I love it.'

We walked across the road down some steps, and staggered across the bank of shingle on to the sand. Kate took her shoes off and poured out a stream of little stones. The sun shone warmly and the tide was out. We walked slowly along the beach for about a mile, jumping over the breakwaters, and then turned and went back. It was a heavenly afternoon.

As we strolled hand in hand up the road towards Kate's car, I saw for the first time that she had parked it only a hundred yards from the Pavilion Plaza Hotel, where I had driven Clifford Tudor from Plumpton ten days earlier.

And talk of the devil, I thought. There he was. The big man was standing on the steps of the hotel, talking to the uniformed doorman. Even at a distance there was no mistaking that size, that dark skin, that important carriage of the head. I watched him idly.

Just before we arrived at Kate's car a taxi came up from behind us, passed us, and drew up outside the Pavilion Plaza. It was a black taxi with a yellow shield on the door, and this time it was close enough for me to read the name: Marconi-cars. I looked quickly at the driver and saw his profile as he went past. I had never seen him before.

Clifford Tudor said a few last words to the doorman, strode across the pavement, and got straight into the taxi without pausing to tell the driver where he wanted to go. The taxi drove off without delay.

'What are you staring at?' said Kate, as we stood beside her car.

'Nothing much,' I said. 'I'll tell you about it if you'd like some tea in the Pavilion Plaza Hotel.'

'That's a dull dump,' she said. 'Aunt Deb approves of it.'

'More sleuthing,' I said.

'All right, then. Got your magnifying glass and bloodhound handy?'

We went into the hotel. Kate said she would go and tidy her hair. While she was gone I asked the young girl in the reception desk if she knew where I could find Clifford Tudor. She fluttered her eyelashes at me and I grinned encouragingly back.

'You've just missed him, I'm afraid,' she said. 'He's gone back to his flat.'

'Does he come here often?' I asked.

She looked at me in surprise. 'I thought you knew. He's on the board of governors. One of the chief shareholders. In fact,' she added with remarkable frankness, 'he very nearly owns this place and has more say in running it than the manager.' It was clear from her voice and manner that she thoroughly approved of Mr Tudor.

'Has he got a car?' I asked.

This was a very odd question, but she prattled on without hesitation. 'Yes, he's got a lovely big car with a long bonnet and lots of chromium. Real classy. But he doesn't use it, of course. Mostly it's taxis for him. Why, just this minute I rang for one of those radio cabs for him. Real useful, they are. You just ring their office and they radio a message to the taxi that's nearest here and in no time at all it's pulling up outside. All the guests use them-'

'Mavis!'

The talkative girl stopped dead and looked round guiltily. A severe girl in her late twenties had come into the reception desk.

'Thank you for relieving me, Mavis. You may go now,' she said.

Mavis gave me a flirting smile and disappeared.

'Now, sir, can I help you?' She was polite enough, but not the type to gossip about her employers.

'Er – can we have afternoon tea here?' I asked.

She glanced at the clock. 'It's a little late for tea, but go along into the lounge and the waiter will attend to you.'

'What did you find out about what?' asked Kate.

I said I was not altogether sure, but that I was interested in anything that had even the remotest connection with the yellow shield taxis or with Bill Davidson, and Clifford Tudor was connected in the most commonplace way with both.

'What next, then?'

'If I could find out who owns the yellow shield taxis -'

'Let's ring them up and ask,' said Kate, standing up. She led the way to the telephone and looked up the number in the directory.

'I'll do it,' she said. 'I'll say I have a complaint to make and I want to write directly to the owners about it.'

She got through to the taxi office and gave a tremendous performance, demanding the names and addresses of the owners, managers and the company's solicitors. Finally, she put down the receiver and looked at me disgustedly.

'They wouldn't tell me a single thing,' she said. ‘But all he would say was, please write to us with the details of your complaint and we will look into it fully. He said it was not the company's policy to disclose the names of its owners and he had no authority to do it. He wouldn't budge an inch.'

'Never mind. It was a darned good try. I didn't really think they would tell you. But it gives me an idea -'

I rang up the Maidenhead police station and asked for Inspector Lodge. He was off duty, I was told. Would I care to leave a message? I would.

I said, 'This is Alan York speaking. Will you please ask Inspector Lodge if he can find out who owns or controls the Marconi-car radio taxi cabs in Brighton? He will know what it is about.'

The voice in Maidenhead said he would give Inspector Lodge the message in the morning. I thanked him and rang off.

Kate was standing close to me in the telephone box. She was wearing a delicate flowery scent, so faint that it was little more than a quiver in the air. I kissed her, gently. Her lips were soft and dry and sweet. She put her hands on my shoulders, and looked into my eyes, and smiled. I kissed her again.

A man opened the door of the telephone box. He laughed when he saw us. 'I'm so sorry - I want to telephone -' We stepped out of the box in confusion.

I looked at my watch. It was nearly half-past six.

'What time does Aunt Deb expect us back?' I asked.

'Dinner is at eight. We've got until then,' said Kate. 'Let's walk through the Lanes and look at the antique shops.'

We went slowly down the back pathways of Brighton, pausing before each brightly lit window to admire the contents. And stopping, too, in one or two corners in the growing dusk, to continue where we had left off in the telephone box. Kate's kisses were sweet and virginal. She was unpractised in love, and though her body trembled once or twice in my arms, there was no passion, no hunger in her response.

At the end of one of the Lanes, while we were discussing whether to go any further, some lights were suddenly switched on behind us. We turned round. The licensée of The Blue Duck was opening his doors for the evening. It looked a cosy place.

'How about a snifter before we go back?' I suggested.

'Lovely,' said Kate. And in this casual inconsequential way we made the most decisive move in our afternoon's sleuthing.

We went into The Blue Duck.