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.
A contrast or discrepancy between what is said and what is meant or between what happens and what is expected to happen in life and in literature. In verbal irony, characters say the opposite of what they mean. In irony of circumstance or situation, the opposite of what is expected occurs. In dramatic irony, a character speaks in ignorance of a situation or event known to the audience or to the other characters. Flannery O'Connor's short stories employ all these forms of irony, as does Poe's "Cask of Amontillado."