‘Good Lord,’ said Alleyn mildly. ‘That’s what the Americans call a break. Coincidence stretches out a long arm. So does the law. “Shake,” says Coincidence. Not such a very long arm, after all, if this pretty fellow is working among one class only and it looks as if he is.’ He shoved a box of cigarettes in Lord Robert’s direction. ‘We had an expert at that letter—the Mrs H-H one you’ve got there. Woolworth paper. She didn’t show us the envelope, of course. Woolworth ink and the sort of nib they use for script writing. It’s square with a feeder. You notice the letters are all neatly fitted between the ruled lines. That and the script nib and the fact that the letters are careful copies of ordinary print completely knocks out any sort of individuality. There were no finger-prints and Mrs Halcut-Hackett hadn’t noticed the postmark. Come in!’

A police constable marched in with a packet of letters, laid them on the desk and marched out again.

‘Half a moment while I have a look at my mail, Bunchy; there may just be—yes, by gum, there is!’

He opened an envelope, glanced at a short note, unfolded an enclosure, raised his eyebrows and handed it to Lord Robert.

‘Wheeoo!’ whistled Lord Robert.

It was a sheet of common ruled paper. Three or four rows of script were fitted neatly between the lines. Lord Robert read aloud:

‘Unforeseen circumstances prevented collection on Monday night. Please leave bag with same sum down between seat and left-hand arm of blue sofa in concert-room, 57 Constance Street, next Thursday afternoon.’

‘Mrs Halcut-Hackett,’ said Alleyn, holding out the note, ‘explains that her unfortunate friend received this letter by yesterday evening’s post. What’s happening on Thursday at 57 Constance Street? Do you know?’

‘Those new concert-rooms. Very smart. It’s another charity show. Tickets on sale everywhere. Three guineas each. Chamber music. Bach. Sirmione Quartette. I’m going.’

‘Bunchy,’ said Alleyn, ‘let nothing wean you from the blue sofa. Talk to Mrs Halcut-Hackett. Share the blue sofa with her and when the austere delights of Bach knock at your heart pay no attention but with the very comment of your soul—’

‘Yes, yes, yes. Don’t quote now, Roderick, or somebody may think you’re a detective.’

‘Blast you!’ said Alleyn.

Lord Robert gave a little crowing laugh and rose from his chair.

‘I’m off,’ he said. Alleyn walked with him into the corridor. They shook hands. Alleyn stood looking after him as he walked away with small steps, a quaint out-of-date figure, black against a window at the end of the long passage. The figure grew smaller and smaller, paused for a second at the end of the passage, turned the corner and was gone.

CHAPTER THREE

Sequence to a Cocktail-party

A FEW DAYS AFTER his visit to the Yard, Lord Robert Gospell attended a cocktail-party given by Mrs Halcut-Hackett for her plain protégée. Who this plain protégée was, nobody seemed to know, but it was generally supposed that Mrs Halcut-Hackett’s object in bringing her out was not entirely philanthropic. At the moment nobody ever remembered the girl’s name but merely recognized her as a kind of coda to Mrs Halcut-Hackett’s social activities.