It does this:
Actor 1 dies, he goes to back of party (all dead actors are still sorted by the "preferred" order)
The second preferred actor is moved up to take his place.
If dead actor returns to life, the party is reordered and Actor 1 returns to being the party leader.
Its for use with the caterpillar script that he is using, and it works. I can supply you with a demo of it working if you still do not understand.