midnight
When the King had retired into his own apartments , Don John found himself unexpectedly alone . Mendoza and the guard had filed into the antechamber , the gentlemen in waiting , being temporarily at liberty , went to the room leading out of it on one side , which was appropriated to their use . The sentries were set at the King 's door , and Mendoza marched his halberdiers out again and off to their quarters , while the servants disappeared , and the hero of the day was left to himself . He smiled at his own surprise , recollecting that he should have ordered his own attendants to be in waiting after the supper , whereas he had dismissed them until midnight . He turned on his heel and walked away to find a quiet place where he might read the paper which had suddenly become of such importance , and paused at a Moorish niche , where Philip had caused a sacred picture to be placed , and before which a hanging silver lamp shed a clear light . The small sheet of paper contained but little writing . There were half a dozen sentences in a clear hand , without any signature -- it was what has since then come to be called an anonymous letter .