midnight
`` Oh ! no ! you are all wrong ; I know what I can do with Henry . '' `` If that is the case , I say good-bye now , for I shall be out of England , if possible , by midnight . You must promise me that you will not only not go to the king at all about this matter , but that you will guard your tongue , jealous of its slightest word , and remember with every breath that on your prudence hangs my life , which , I know , is dear to you . Do you promise ? If you do not , I must fly ; so you will lose me one way or the other , if you tell the king ; either by my flight or by my death . ''