The magician's assistant sits down in the very innocent open looking framework. Her head is then covered with a silk cloth. The magician then introduces a blade and proceeds to amputate his assistants head.
The magician then causes the silk covered head to float around the stage and all the time that this is happening the assistant is sitting on the chair with no head!
After a short while the assistants head is placed back on to her body, the silk is removed and the assistant is back in one piece!