The magician asks someone in the audience who has a pair of handcuffs to come up on stage. The magician inspects the handcuffs and, after making sure they are in working order, asks the spectator to put them on (the magician).
Once shackled, the magician's hands are placed into a bag held by an assistant. A moment later, the magician's hands emerge from the bag, freed and holding the still-locked handcuffs in one hand.
There are three methods for escaping from borrowed handcuffs.
The "wrist" method
A magician using the wrist method tricks the spectator into not completely closing the handcuffs about the magician's wrists. This is done by a) getting the spectator to fasten the handcuffs over the magician's jacket sleeves, b) wearing thick wristbands over which the cuffs are fastened, or c) wearing a very thick false wrist prosthesis. Any of these methods leaves the handcuffs open enough that the magician's hands can just slip through once they are hidden within the bag.
The "dairy" method
Before performing the trick, the magician coats both wrists with a large amount of butter (not margarine, although some type of clear oil may be substituted). This preparation allows the hands to slip easily from the cuffs. The only down side is that the trick must be performed quickly because under hot stage lights the magician's wrists can quickly turn rancid.
The "key" method
If the magician's assistant and the person who will donate the handcuffs are of compatible genders and orientations, the magician may choose to use the key method. This involves the assistant starting up a relationship with the spectator in the days before the performance with the sole goal of obtaining the handcuff key (perhaps during a "kinky" moment). During the subsequent performance, the assistant uses the key to unlock the magician while pretending to put the cuffed hands into the bag.
Magicians who do not wish to borrow handcuffs from a member of the audience or who are performing for a group unlikely to have handcuffs ready (e.g., federal prison inmates or Girlscouts) may wish to rely on trick handcuffs. Trick handcuffs are made in such a way that they can be easily removed, even without a key. These handcuffs can be used not only for the routine described here, but for a wide variety of stunts and escapes.
The most popular fake handcuffs include: