I hear the beaten drum.  
One character in this work says "our flesh and blood is grown so vile, my lord, that it doth hate what gets it" and concludes one monologue with the line "As flies to wanton boys are we to the gods.  They kill us for their sport".  That character would later claim that "woes by wrong imaginations lost the knowledge of themselves" before he hears a drum and another character replies "Give me your hand.  Far off methinks I hear the beaten drum.  Come, father, I'll bestow you with a friend".  Those characters, Edgar and the Earl of Gloucester, had earlier been out on the heath during a storm with the title character of this work when he denounced his daughters, about one of whom he had earlier said "how sharper than a serpent's tooth it is to have a thankless child!"  For 10 points—name this Shakespearean tragedy.
One character in this work says "our flesh and blood is grown so vile, my lord, that it doth hate what gets it" and concludes one monologue with the line "
King {Lear}