The door was locked and the old detective getting out his skeleton keys went at the job of opening it vigorously.
He quickly succeeded.
A narrow, dark staircase leading up lay beyond; leaving the door unlocked, Old King Brady pressed on to the top flight, no great distance, coming out upon a semi-circular platform where there were three doors.
There was no light here.
The old detective flashed his electric lantern around.
"Your Chinese puzzle isn't it, Mr. Brady," whispered Leggett. "Is there any end to the mysteries with which these Chinks like to surround themselves?"
"None, absolutely none," replied the old detective. "It makes one tired to try to follow their curves. But listen a moment. We may catch on to something."
"It's a blame sight more likely that someone will catch on to us," growled Leggett.
"Hush! Hush! Listen!"
He had scarcely spoken when someone behind the middle door called out in a loud voice in English: