Where is the thieves' guild?

Have you met any of your brethren at night?

There's a trap set by thieves inside the walls of Spielburg.

Thieves are most active at night.

See that flashing light in the back alley?

Once you investigate, some thieves will appear.

Now's the time to make the sign (click the hand on the thief).  You will
learn the location and password to the guild.