This is from Dutch Council MELE rules (which I always trusted so far):
Its Player 1s turn. Player 2 plays Sudden Call as hazard. So this means that Player 1 must fit into the conditions to call (exhausted and 25+ MP) and player 2 gets one last turn?SUDDEN CALL USED AS A HAZARD
In addition to the normal situations outlined in the Starter Game, the Audience With Sauron is called when one of the following occurs:
· If your opponent's play deck has been exhausted and you play a Sudden Call card as a hazard during one of his turns, the audience starts following your next turn (i.e., you get one last turn).
· If your opponent has at least 20 marshalling points and you play a Sudden Call card as a hazard during one of his turns, the audience starts following your next turn (i.e., you get one last turn).