When the detectives reached the spot he was gone.

They made a quick search and went all over the hotel.

They made inquiries of bell-boys and other attaches.

But in vain.

It convinced them that they were truly up against a hard game.

The trio seemed possessed of a supernatural faculty for making themselves invisible at will.

Completely mystified, the Bradys sat down in the hotel lobby and tried to think.

It was a conundrum.

The foes were close upon their heels and could not be shaken off or decoyed. They were as elusive as the will-o’-the-wisp.

It was easy to understand their game.