This is probably one of the best versions of Annemann's classic "Seven Keys to Baldpate".

Here's what happens: They show the audience a massive 350-gram "Old English" padlock made of steel and brass, the approximately 10-cm-wide 660 Mammoth version. Six keys are presented and tried out: No one is able to open the lock.

But there is a 7th key, which is the only one that fits the lock.

Now a woman's ring is placed on the lock's shackle. All seven keys are shuffled, making it impossible to know which one is the right one. Six spectators each choose a key (no force!), and the woman receives the last remaining one. And lo and behold, she has chosen the only key that opens the lock!

You'll receive quality props so perfectly prepared that you'll be holding a small mechanical miracle in your hands, one that practically performs the described effect all by itself. Everything can happen exclusively in the hands of spectators (who are, of course, uninitiated), allowing you to concentrate fully on the process and the presentation. Various performance variations are possible; in one, designed by Edwin Hooper , you don't even have to touch the lock or key, yet everything works as you wish.

David DeVal's lock was made entirely of brass, and the keys could only be handed over one at a time. Lupo's lock is made of steel and brass, and all the keys look different, making it easy to hand them over or show them together.