"A single word may solve this mystery.

He has the word.

I'd be a fool to let the night go by--Ah! what's that ?" The telephone bell had rung again.

A message from the office this time.

A note had just been handed in for Mr.Ransom; should they send it up?
Gerridge was at the 'phone.
"Instantly," he shouted down, "and be sure you hold the messenger.