The Runaway Knot

Effect:
The performer takes a piece of rope and allows the spectator to cut it in two. The two ends of the rope are then tied together, and then held up. The magician slides the knot down the length of the rope, and makes it vanish.

Secret:
Take a three or four foot piece of rope and tie the ends together to form a loop. Start by holding the rope in your right hand, laying the knot of the loop across your face up palm. Take your left hand, palm face down, and place your hand into the backside of the loop and grab the other half of the rope with your left hand. Bring your hands together and lay the other piece of rope in your right hand, twisting your hands back to their natural position. This should cross the strings twice forming a small lock, immediately cover this lock with your right hand as you are bringing your hands together. Hold the rope with your left hand a few inches away from your right, and ask a spectator to cut the rope in between your hands. Covering the lock with your right hand still, it looks like two pieces of rope of the same size, hanging side by side. Now tie the two loose ends hanging from the top of your hand together without revealing the hidden lock, this knot can now be slid up and down the rope. Slide the knot off the rope to finish.