They soon were convinced nobody was in the salesroom. They came to the partition in the rear, and found the door partly open. Here they redoubled their caution. If the Black Star was present he was somewhere behind that partition.

Riley opened the door carefully, and they stepped inside. Here they found a dim light, too, coming in from the street. Here were tables where diamonds were displayed to purchasing merchants, sets of mirrors so an employee could see the entire interior at a glance, and, at the opposite end of the room, the door to the great vault of Jones & Co.—the vault that held always a fortune in jewels and was supposed to be impregnable.

They crouched—and looked. Verbeck drew in his breath sharply.

The door of the vault stood open.

In it, his back toward them, gloating over a handful of jewels, was—the Black Star!

As they watched, they heard him chuckle softly, saw him throw up his head—and walk into the vault!

[CHAPTER XXIV—HOW IT ENDED]

Verbeck’s whisper was so low that Riley and Muggs scarcely could hear it, yet they could detect the note of exultation:

“We’ve got him!”

That was all, and then they started to creep forward, their eyes on the vault, from which not a bit of light came. The Back Star evidently was working in the dark.