I’m hearing the word ‘irony’ bandied around this site a lot, and I’m not actually sure there’s a concise definition of the word or in fact it is necessary for use in log lines. I know Blake Snyder says log lines should have ‘irony’ but I’m not even sure he was using the term correctly. In fact his book way over simplifies the art of screenwriting. Truby nor McKee uses the term at all. NOT all films / stories are ironic, therefore not all log lines need irony.

There are, it seems, 4 variations of the word irony:

‘Verbal irony’ is a disparity of expression and intention: when a speaker says one thing but means another, or when a literal meaning is contrary to its intended effect. An example of this is when someone says “Oh, that’s beautiful”, when what they mean (probably conveyed by their tone) is they find “that” quite ugly.

‘Dramatic irony’ is a disparity of awareness between actor and observer: when words and actions possess significance that the listener or audience understands, but the speaker or character does not, for example when a character says to another “I’ll see you tomorrow!” when the audience (but not the character) knows that the character will die before morning.

‘Situational irony’ is the disparity of intention and result: when the result of an action is contrary to the desired or expected effect. Being “shot with one’s own gun”, or “hoisted with one’s own petard” are popular formulations of the basic idea of situational irony.[this quote needs a citation][dubious ? discuss]

‘Cosmic irony’ is disparity between human desires and the harsh realities of the outside world. By some definitions, situational irony and cosmic irony are not irony at all.

If any form of irony is used in story I would suggest it is dramatic irony, something we know that a character doesn’t – aka ‘superior position’.

Dramatic irony

This type of irony is the device of giving the spectator an item of information that at least one of the characters in the narrative is unaware of (at least consciously), thus placing the audience a step ahead (SUPERIOR POSITION) of at least one of the characters. Dramatic irony has three stages?installation, exploitation, and resolution (often also called preparation, suspension, and resolution)?producing dramatic conflict in what one character relies or appears to rely upon, the contrary of which is known by the audience; sometimes to other characters, to be true. In summary, it means that the reader/watcher/listener knows something that one or more of the characters in the piece is not aware of. (SUPERIOR POSITION)

For example:

In City Lights the audience knows that Charlie Chaplin’s character is not a millionaire, but the blind flower girl (Virginia Cherrill) believes him to be rich.
In North by Northwest, the audience knows that Roger Thornhill (Cary Grant) is not Kaplan; Vandamm (James Mason) and his accomplices do not. The audience also knows that Kaplan is a fictitious agent invented by the CIA; Roger (initially) and Vandamm (throughout) do not.
In Oedipus the King, the reader knows that Oedipus himself is the murderer that he is seeking; Oedipus, Creon and Jocasta do not.
In Othello, the audience knows that Desdemona has been faithful to Othello, but Othello does not. The audience also knows that Iago is scheming to bring about Othello’s downfall, a fact hidden from Othello, Desdemona, Cassio and Roderigo.
In The Cask of Amontillado, the reader knows that Montresor is planning on murdering Fortunato, while Fortunato believes they are friends.
In The Truman Show, the viewer is aware that Truman is on a television show, but Truman himself only gradually learns this.
In Romeo and Juliet, the other characters in the cast think Juliet is dead, but the audience knows she only took a sleeping potion.
In Forrest Gump, the audience knows the historical significance of the characters and scenarios Forrest Gump finds himself in, but he often does not.
In The Lion King, Simba goes throughout the film until near its end believing that he was responsible for his father, Mufasa’s, death. However, the audience knows that it was actually Simba’s uncle Scar who killed Mufasa.

FROM: http://en.wikipedia.org/wiki/Irony

Let’s be clear about how irony is to be used in log-lines as I think the word can be both complex and confusing.