The next twenty minutes passed slowly, the ten minutes after that more slowly still. Dymchurch was striding up and down with a face that grew darker and darker. Once he turned menacingly on Tommy.

‘If you have dared to double-cross us,’ he growled.

‘If we’d had a pack of cards here, we might have had a game of picquet to pass the time,’ drawled Tommy. ‘Women always keep one waiting. I hope you’re not going to be unkind to little Tuppence when she comes?’

‘Oh, no,’ said Dymchurch. ‘We shall arrange for you to go to the same place—together.’

‘Will you, you swine,’ said Tommy under his breath.

Suddenly there was a stir in the outer office. A man whom Tommy had not yet seen poked his head in and growled something in Russian.

‘Good,’ said Dymchurch. ‘She is coming—and coming alone.’

For a moment a faint anxiety caught at Tommy’s heart.

The next minute he heard Tuppence’s voice.

‘Oh! there you are, Inspector Dymchurch. I’ve brought the letter. Where is Francis?’

With the last words she came through the door, and Vassilly sprang on her from behind, clapping his hand over her mouth. Dymchurch tore the handbag from her grasp and turned over its contents in a frenzied search.

Suddenly he uttered an ejaculation of delight and held up a blue envelope with a Russian stamp on it. Coggins gave a hoarse shout.

And just in that minute of triumph the other door, the door into Tuppence’s own office, opened noiselessly and Inspector Marriot and two men armed with revolvers stepped into the room, with the sharp command: ‘Hands up.’

There was no fight. The others were taken at a hopeless disadvantage. Dymchurch’s automatic lay on the table, and the two others were not armed.

‘A very nice little haul,’ said Inspector Marriot with approval, as he snapped the last pair of handcuffs. ‘And we’ll have more as time goes on, I hope.’

White with rage, Dymchurch glared at Tuppence.

‘You little devil,’ he snarled. ‘It was you put them on to us.’

Tuppence laughed.

‘It wasn’t all my doing. I ought to have guessed, I admit, when you brought in the number sixteen this afternoon. But it was Tommy’s note clinched matters. I rang up Inspector Marriot, got Albert to meet him with the duplicate key of the office, and came along myself with the empty blue envelope in my bag. The letter I forwarded according to my instructions as soon as I had parted with you two this afternoon.’

But one word had caught the other’s attention.

‘Tommy?’ he queried.

Tommy, who had just been released from his bonds, came towards them.

‘Well done, brother Francis,’ he said to Tuppence, taking both her hands in his. And to Dymchurch: ‘As I told you, my dear fellow, you really ought to read the classics.’

The Incredible Theft