'Mr Abney!'

It was the person standing behind me who spoke. Till now he or she
had remained a silent spectator, waiting, I suppose, for a lull in
the conversation.

They jumped, all together, like a well-trained chorus.

'Who is that?' cried Mr Abney. I could tell by the sound of his
voice that his nerves were on wires. 'Who was that who spoke?'

'Shall I telephone for the police?' asked Glossop. Ignored.

'I am Mrs Sheridan, Mr Abney. You were expecting me to-night.'

'Mrs Sheridan? Mrs Sher--I expected you in a cab. I expected you
in--ah--in fact, a cab.'

'I walked.'

I had a curious sensation of having heard the voice before. When
she had told me not to move, she had spoken in a whisper--or, to
me, in my dazed state, it had sounded like a whisper--but now she
was raising her voice, and there was a note in it that seemed
familiar. It stirred some chord in my memory, and I waited to hear
it again.

When it came it brought the same sensation, but nothing more
definite. It left me groping for the clue.