They left the restaurant and then went on to a night-club, where they passed a pleasant hour or two. The music was lively, the place was crowded with fashionable people, and there was plenty to observe and comment upon without any thoughts of murder intruding to spoil their enjoyment. Their revelry was not destined to continue, however, for they were sitting at their table and considering a dance when Gertie’s eyes widened suddenly.
‘Look!’ she said.
She nodded at something over Freddy’s shoulder. Freddy turned and saw that Alida Westray was just entering the night-club, followed, to his astonishment, by Leslie Penbrigg himself.
‘Well, I’ll be damned! So the old chap has finally plucked up the courage to speak,’ murmured Freddy, momentarily forgetting that the ‘old chap’ in question was quite possibly a murderer.
Alida had spotted them, and was seen in consultation with Penbrigg, and at length they were seated at the table next to Freddy and Gertie’s.
‘We went to the theatre to see that new play, and then had a very late dinner,’ said Alida. ‘The play was rather good, wasn’t it, Leslie?’
‘Oh—er—rather,’ said Leslie Penbrigg, who did not appear to have become any less tongue-tied.
Alida seemed in a chatty mood. She spent some time telling them about the play, then said, as though she had just remembered:
‘By the way, Freddy, I thought Father might know something about that notebook you mentioned, so I asked him this morning, but he said he knew nothing about it.’
At her words Freddy and Gertie froze momentarily, then Gertie kicked Freddy under the table as Leslie Penbrigg looked up.
‘Which notebook?’ he said. He spoke in his usual pleasant manner, and his face wore an expression of mild curiosity.
‘You remember Mr. Finkley, don’t you?’ said Alida, with blithe unawareness that she was saying anything of importance. ‘Apparently he left a notebook full of drawings behind him, and Mrs. Finkley gave it to Douglas just before he died. Freddy was wondering what had happened to it.’
Leslie Penbrigg regarded Freddy blandly.
‘A notebook of drawings, eh? I expect it’s lying around somewhere,’ he said.
‘Yes, I expect it is,’ said Freddy.
There was a short silence, then Gertie said:
‘What time is it, Freddy?’
‘One o’clock,’ he replied.
She gasped.
‘Oh, goodness! I promised faithfully I’d be back before midnight. You’d better take me home.’
‘What?’ said Freddy, surprised, but she was glaring at him meaningfully. ‘Oh—er—very well.’
The bill was settled, then they said their goodbyes to Penbrigg and Alida and rose to leave. Gertie stumbled heavily against Penbrigg’s chair as they passed.
‘Careful, old girl. I told you not to have that third glass of champagne,’ said Freddy. They went outside, and he gave a grimace. ‘Damn! Of all the rotten luck. Why didn’t I think to tell her to keep it quiet? Now he’ll know we’re after him and he’ll hide the thing as soon as he can.’
‘Yes, that’s what I thought,’ said Gertie. ‘That’s why I stole his keys. Now we can go and search his workshop.’
Freddy regarded her in astonishment. Sure enough, she was holding up a bunch of keys and looking very pleased with herself.
‘Good Lord! Is that what you were doing when you were lumbering about in there? Picking his pocket?’
‘Rather a good job on my part, don’t you think?’ said Gertie.
‘Remind me to introduce you to a friend of mine,’ said Freddy.
‘Who’s that? Never mind, there’s no time. Let’s go!’
‘What, now? You’re not exactly suitably dressed for breaking and entering.’
‘Nor are you, for that matter, but we haven’t a minute to lose! We have to get the notebook before Penbrigg does.’
Before he could object she had flagged down a taxi and jumped in.
‘Take me to the aeroplane factory,’ she said grandly. ‘I don’t know where it is.’
The taxi driver turned an appealing gaze on Freddy.
‘Hammersmith,’ said Freddy.
‘And make it quick,’ said Gertie.
The taxi pulled away, and in a very short time they had reached their destination. The driver set them down on King Street, since they did not wish to draw attention to themselves, and they alighted and set off on the short walk to the factory.
‘How are we going to get in through the gate?’ said Gertie as they walked. ‘I expect there’ll be a night-watchman.’
‘Yes, and I don’t suppose he’ll just let us in through the front door.’ Freddy was trying to remember what he had seen on his last visit. Penbrigg’s workshop had been in a back yard surrounded by high walls. ‘I think there might be a back gate,’ he said. ‘We’ll just have to hope one of these keys fits.’
They had now passed into a quiet area which was unlit by street-lamps. It was dark, but the moon was not long past full, which allowed them to see where they were going. They arrived at the front gates of the factory and peeped through. The windows were in darkness, but one light had been left on over the entrance.
‘Can’t see anyone,’ said Freddy at last. ‘Let’s go and find a back gate. This way.’
They turned right and entered a tiny alley which skirted the boundary of the factory. Here the moonlight could not penetrate and it was much darker. After a few yards Freddy stopped.
‘I think the workshop is about here,’ he said. He looked up. ‘Hmm. An eight-foot wall with broken glass along it. Nothing doing there. Now, is there a gate or not?’
‘Of course there’s a gate,’ said Gertie. ‘There must be.’
They carried on along the alley and then turned left, still following the factory wall. Here the alley became a narrow path, bounded on one side by thick bushes.
‘There it is!’ she hissed.
Sure enough, a little farther ahead, the wall was broken by a solid wooden gate, which was firmly shut. A man in a uniform and peaked cap was leaning against the gate, idly playing a torch over the bushes and smoking a cigarette. As they watched, the torch beam headed towards them, and they ducked hurriedly back into the alley.
‘Bother!’ whispered Gertie. ‘Now what do we do?’
‘Wait for him to finish his cigarette, I suppose.’
They waited. After a minute or two, Freddy peeped around the corner, and to his shock and dismay saw that the night-watchman was only a few yards away, heading towards them. He had approached so quietly that they had not heard him. He withdrew his head immediately and grabbed Gertie’s arm, then indicated with frantic gestures that it was time to retreat. Gertie gave a silent gasp and glanced towards the entrance of the alley, preparing to make a run for it. But there was no time: the darkness was already becoming thinner as the torch beam approached, and they could hear the man clearing his throat. He could not be more than a few yards away. It was too late to escape now. There was no alternative; desperate measures were required. Without ceremony Freddy pulled Gertie towards him.
‘Sorry,’ he said hastily, and kissed her.
The night-watchman rounded the corner, gave an appreciative snigger as he passed, and walked off, breaking into a cheery whistle as he did so. Freddy let Gertie go. There was a short, breathless silence.
‘Are you quite sure it wasn’t Mungo?’ she said at last.
‘I suppose it might have been,’ said Freddy.
‘Do it again, just to make sure.’
Freddy obliged.
‘Well, this is all splendid fun, but we are here for a reason,’ she said after a little while. ‘Hadn’t we better go and try the gate before he comes back?’
‘Ah, yes,’ said Freddy, recollecting himself.
The night-watchman was nowhere to be seen, so he let her go and they returned to the gate, Gertie smoothing down her frock and fighting an inclination to giggle. She brought out the keys from her handbag and they picked the one that looked most likely. Freddy tried it, and after a little struggle it turned in the lock. Gertie beamed at him in excitement and pushed at the gate, which creaked slightly. On the other side was the overgrown yard which Freddy had already seen on the day he visited Penbrigg.
‘It’s over here,’ he whispered. He took her hand and they crept across to the low building inside which was Penbrigg’s workshop. The keys were produced again and an entry effected. The waning moon cast a thin light through the small windows, and as far as Freddy could see in the dim light, the place was as untidy as ever.
‘A torch would be preferable, but I’m afraid we’ll have to make do with the moonlight,’ he said. ‘Be careful where you put your feet.’
‘I see what you mean about all the scraps of metal on the floor,’ said Gertie, picking her way gingerly across the room. ‘Now, where shall we look first?’
‘I suggest the drawers.’
It was not easy to search in the near-darkness, but they did their best. Most of the drawers were not locked, but there was such a jumble of things inside them that it quickly became clear it would be almost impossible to find anything in the time available to them, unless they had a stroke of good luck. After a fruitless search lasting several minutes, Gertie began trying the doors of the cupboards. She opened one and found it was full of piles of loose paper, jars of screws, twisted bits of metal and machine parts, but nothing that looked like a notebook. She tried the next one.
‘Oh, this one is locked,’ she said. ‘Do we have the key to this cupboard?’
Freddy looked up from the drawer he was searching and came over to see. There was a small key which looked as though it might fit. He tried it, and it turned easily in the lock. He opened the door, and gave an exclamation.
‘Well, well, what do we have here?’ he said, bringing something out. It was a pair of men’s shoes.
‘Doug’s shoes!’ said Gertie.
Freddy turned them over and took them across to the window to examine the soles.
‘I rather wonder sometimes whether I’m not a genius,’ he said.
Gertie looked. Wedged tightly into the heel was a small piece of metal, with the word ‘Westray’ clearly stamped on it.
‘Sparking plug electrode,’ said Freddy. ‘He said they kept snapping off. I don’t suppose the police would have had the sense to realize that Douglas must have picked it up that evening since the shoes were new, but he couldn’t take any chances.’
‘Now for the notebook.’ Gertie went back to the cupboard and rummaged around. ‘Nothing,’ she said, disappointed. ‘Is there anything on the top shelf? I can’t reach.’
Freddy put his hand up and felt about, then brought down a sheaf of papers. In among them was a battered old notebook without a cover. He took it across to the window and squinted at it closely. The paper was squared, and was covered with drawings and diagrams and notes. He flicked through the pages.
‘Good old Finkley,’ he said at last. ‘He’s even dated his ideas. Aha! Look at this.’
Gertie peered at the page he was indicating.
‘What is it? An aeroplane wing?’
‘With a slot,’ said Freddy. ‘And some equations that I shall pretend to understand. And—most importantly of all—a date of August two years ago, some time before the Woodville Prize.’
Gertie took the notebook and began to look through it, then started violently and looked around.
‘What is it?’ said Freddy.
‘Did you hear that noise?’ she whispered.
‘Which noise?’ he said, lowering his voice.
‘I don’t know. A sort of scraping sound. It came from quite nearby.’
They listened, but heard nothing. Gertie glanced towards the door to Penbrigg’s office and pointed. It was slightly ajar. They looked at one another.
‘Is it Penbrigg?’ whispered Gertie.
Freddy shook his head. There was not time for Penbrigg to have got there before them.
‘Just a mouse, I expect,’ he said. ‘I forgot about that office. I wonder if there’s anything else in there we ought to see.’
He went across and pushed the door open, then started back as a shadow loomed up in the darkness.
‘You’d have done much better to keep your nose out of things,’ said a voice. There was a click and a lamp was switched on, and they gasped as a familiar figure came towards them.
‘Captain Dauncey!’ exclaimed Gertie.