Corrected entry: When Abigail loosens the rope that is securing Sommerfield's arms to the wall, she pulls on the main loop, revealing that it's just a slip knot. Sommerfield could have easily freed herself, or at least the weight of her body should have pulled those loose.
Kristal
16th Dec 2004
Correction: Cowboys in the old west often used a knot to tie up horses that could be untied by pulling on one end but could not come loose when the horse pulls on the other.