From Facing Lines or other applicable formations.
Centers Touch 1/4, 
  Cross Concentric 
  Vertical Tag The Line,
  Leaders Peel Left, Trailers Peel Right to end as a Couple (as in
  Sets In Motion)
  as the Outsides Circulate once and a half, Hinge,
  Cross Concentric Vertical 1/2 Tag, and Face In.
Facing Lines ends in a Double Pass Thru.
Notes:
- 
When Plan Ahead is done from formations other than Facing Lines
    (e.g., Inverted Lines with the Ends Facing Out):
    the Ends must be careful to Circulate 1 & 1/2 before the Hinge.  
    There is a tendency for the Ends to Hinge with the first dancer they meet.
 - 
We have recently learned that there are callers who believe that the
    first part for the Centers is a 1/2 Circulate and Hinge (instead of
    Touch 1/4).  This can lead to several other possible starting
    formations.