As Polonius leaves, Rosencrantz and Guildenstern enter, and Hamlet seems pleased to see them. They discuss Hamlet’s unhappiness about recent affairs in Denmark. Hamlet asks why they have come. Sheepishly, the two men claim they have come merely to visit Hamlet, but he sternly declares that he knows that the king and queen sent for them. They confess this to be true, and Hamlet says that he knows why: because he has lost all of his joy and descended into a state of melancholy in which everything (and everyone) appears sterile and worthless.
Shakespeare's Hamlet is a play rife with moral dilemmas. Religious codes often clash with desires and instinctual feelings in the minds of the characters, calling into question which courses of action are truly the righteous paths. In Hamlet's case, such conundrums are debilitating and cause a frustrating, eventually fatal lack of action. Indeed, the absence of moral clarity in the play is arguably the root of most of the tragedy that is played out in the final scenes. Because of this, the issues in Hamlet provide an excellent basis from which to delve into an exploration of how religion motivates human actions. The characters' dilemmas concerning two great moral questions, suicide and murder, demonstrate the centrality of this motivation, both within the confines of the play and within the larger scope of human society.
This is perhaps one of Shakespeare's more interesting plays, if you will. In comparison to Macbeth it isn't quite the walk in the park.
I think conceptually it enables the reader to see that characters can influence characters to such a degree that the original traits are masked and changed. Tragedy in this play is definitely a main component - and a great emphasis that perhaps the villain doesn't always find their true defeat. In a way, wasn't the "villain" successful? He lied to everyone and pretty much killed whomever got in his way.