How does the mood affect the play Hamlet?

Mood is the emotional landscape of a piece. It is just like the moods you have. What kind of mood do you get into when you read the play? The mood of Hamlet is at times dark and suspenseful; at others, humorous. 

When the ghost arrives, the mood is both suspenseful and eerie. The reader is not sure what is going to happen. Ghosts do not just wander into most of our lives. Here is a ghost telling Hamlet that his uncle killed his father! 

When the ghost appears, Horatio tries to speak to it. He has been elected because he is a scholar. The guards seem to think the ghost will chat with him. Just the same, Horatio is kind of spooked.

HORATIO

Re-enter Ghost

I'll cross it, though it blast me. Stay, illusion!
If thou hast any sound, or use of voice,
Speak to me:
If there be any good thing to be done,
That may to thee do ease and grace to me,
Speak to me (Act I, Scene 1).

Their repeated efforts to speak to the ghost, and its disappearances and reappearances leading up to Hamlet talking to it, create the spooky and ominous mood. The ghost’s insistence on revenge also creates a feeling of anticipation. 

Hamlet’s crazy act is serious business, but it is also pretty funny at times. The moments of humor actually add to the play because they create comic relief and move the plot along. For example, when Hamlet refuses to tell where Polonius’s body is, it is both tragic and funny. 

KING CLAUDIUS

Now, Hamlet, where's Polonius?

HAMLET

At supper.

KING CLAUDIUS

At supper! where?

HAMLET

Not where he eats, but where he is eaten: a certain
convocation of politic worms are e'en at him (Act IV, Scene 3).

There are additional scenes of humor when Hamlet is in the graveyard, where Shakespeare makes interesting social commentary that is also funny. The message is that we all die, and everyone goes into the ground equal. If you are important, however, you get special privileges. If you're not, once you are buried it does not necessarily mean you will stay there! 

The ending of the play is very dramatic. By the time the last scene has ended, almost everyone is dead. The audience here will be highly involved, and the mood is frenzied and sad. Hamlet gets his revenge on Claudius, Gertrude dies, Hamlet is poisoned with the sword, and Laertes follows his father and sister into death. 

The shifts in mood throughout the play always accompany the action. Nothing is unintentional. Even the comic relief serves a purpose. Therefore, the play is an emotional roller coaster ride, and great entertainment.