’"DEAR SIR,

’"I have reason to think that you may be interested in some extraordinary information which I have in my possession concerning Camilla Tudor, who is supposed to have been buried at Brompton Cemetery in July last year.  If I am right, perhaps you will accompany the bearer to my rooms.  At present I will not disclose my name.

    ’"Yours, etc.”

’Put any initials you like.  Address it to Louis Ravengar, Esquire.  Now listen to me.  Go down to the auto garage, and choose a good man to take the note instantly; a second man must go with him.  If they bring back Ravengar, he is to be taken to No. 6, Blair Street, shown upstairs, and brought along the bridge-passage into the building.  It will be quite dark, and he will never guess.  If necessary, he must be brought to me by force, once he is inside.  Have two or three porters in attendance to see to that.  But if it’s managed properly, he’ll come without a suspicion, and he’ll be finely surprised when he finds that the long passage ends in just this room.  Come back to me as soon as you’ve attended to that.’

‘Yes, sir,’ said Simon, quite mystified, but none the less enchanted to see Hugo so actively the old Hugo.

In ten minutes he had returned, and was beginning to relate new facts which he had learnt while downstairs.

‘Stop!’ said Hugo.  ’Don’t worry me with needless details.  I know enough.  And don’t ask me any questions.  We can’t hope to remedy the state of affairs to-day.  Nevertheless, we can do something for to-morrow.  I must have Mr. Bentley, the drapery manager, brought here before six o’clock.  He must be found.’

‘He is found, sir.  He has shot himself in his house in Pimlico Road.’

Hugo started.

‘Ah!’ was all he said at first.  He added dryly:  ‘Good!  And Brown?’

‘I have no news of him, sir.  He’s vanished.’

’Telephone down to the press department that Mr. Aked must come up to see me at seven o’clock precisely, and, in the meantime, he must secure an extra half-page in all to-morrow’s papers.’

‘Yes, sir.’

’And after closing-time the entire staff must assemble, the men in the carpet-rooms, and the women in the central restaurant—­or what’s left of it.  I shall speak to them.  Have notices put in the common-rooms.’

‘Yes, sir.’

’And send me all the buyers from the drapery department.  They must go round and buy every silvered fox-stole in London to-night, at no matter what price.’

‘Certainly, sir.’

’And telephone to Y.Z. that I shall be down there as soon as I can about these things.’

He touched the pile of yellow envelopes.  Y.Z. was the name always given to the detectives’ private room.

‘Precisely, sir.’

‘That’s all.’

Simon Shawn gathered that his master had a very definite clue to the origin of the unique and fatal events of that day, and that all dark places were about to be made light with a blinding light.