drop-dead list

They identified eight general categories of deep secrets, promptly dubbed the "drop-dead list," some elements of which are deemed so exceedingly secret that officials dare not even speak their names.

If any documents or testimony relating to a subject on the drop-dead list seemed likely to come up, the trial would halt while all parties tried to settle the question behind closed doors.

There are times, though, admits Elsa, when a girl's drop-dead list gets completely out of hand: "I've said so many nice things and so many mean things about so many famous people, I often have to read my book to find out who it is I don't like."