Oct 24, 2011

Trilogies and Tetralogies

This weekend my wife and I will be at Gaelcon, the largest gaming convention in Ireland. I typically run a roleplaying game at the convention. Since running rpgs features a lot of consideration for story structure and offers a great proving ground for plot ideas and usage of themes and tropes, I thought I'd spend this week talking about certain aspects of storytelling structure.

For today's post, I'm dealing with two of the most common series formats, the trilogy and the tetralogy, going all the way back to ancient Greek theatre.

Ancient Greek theatre was often crafted and performed in a 3-play format. We get our term "trilogy" from this, when audiences would spend a day at the theatre, seeing three tragedies forming one over-arcing story, accompanied by a more comedic "satyr" play.

The trilogy has remained with us to this day, becoming the most common form of storytelling in any genre and format. Even within standalone novels and movies, we talk about the 3-act structure. In a typical trilogy today, the first story will handle the introduction of the heroes, the villains, and establish both the state of affairs from before the beginning of the story, and a new status quo after the villain's defeat. The second story further develops the nature of the heroes' struggle and often reveals more of the villain's motivations, often culminating in an ending that pitches the heroes into their darkest hour. Finally, the third part of the story will bring elements of the previous instalments together as the heroes come to their final realisations, unlocking their true strength and finally overcoming the villain.

A four-part series is properly termed a tetralogy, coming from the Greek "tetra." When the trilogy of tragedies in Greek theatre is taken together with its accompanying satyr play, it forms a tetralogy. Unfortunately no complete ancient Greek tetralogy survives. The only Greek trilogy which survives is the Orestia. Recently movie trilogies have been revisited, turning them into tetralogies. Examples include the Rambo, Die Hard and Indiana Jones series. However the term quadrilogy, first actually recorded in 1865, is usually used instead when marketing 4-part movie series.

The structure of a tetralogy is more difficult to define. In planned 4-part series, tetralogies often eschew convention and while the third part may resolve many of the challenges faced by the heroes, the final victory will be delayed until the fourth part, or a previous lesser antagonist, or even an entirely new threat, may rise to challenge the heroes one last time.

Other formats of set series include a diology, pentalogy, hexalogy, heptalogy, octalogy, ennealogy and decalogy. These become ever more difficult to describe in terms of a predictable act structure, and usually become either more or less standalone stories connected by common characters and possibly an over-arcing metaplot, or simply one ongoing story broken up into component parts. In most cases, once a series has gone on long enough to move beyond five or six instalments, it can become difficult even for the author to define what kind of series it is until the final instalment has been released.

Do you have any favourite series? Is there a particular series length you find you prefer over others?


  1. I wouldn't say I have an ultimate series length, as long as it stays fresh, fun (if it's that kind of series) and interesting. When the story or the characters get stale, it's time to be done (preferably before that happens).

    I like the Women of the Otherworld series, because it's the only one I personally know of (doesn't mean there aren't others, just not ones I'm aware of) that changes the main characters each time. Each book is a new story with a different main character, though they're all connected, and I think that's a good way to keep things fresh. Kelley Armstrong has announced she's ending the series soon, and that makes me sad, which tells me it's a successful time to end it. The characters didn't get a chance to get old for me, and it kept me wanting my favorites back longer.

  2. That sounds like a great way to keep a series feeling fresh. I love that bittersweet feeling when a beloved story comes to an end. It's sad to say goodbye to the characters, but that's so much better than seeing a series drag on past its time.

    You're right, so long as people are still drawn to the characters and story, it can keep going.

  3. We can learn a lot about story structure from movies. It's been a long time since I studied Greek drama, so this brings some of what I learned back. The Indiana Jones series played out well, I thought, except for the second one that I didn't like at all.

    Enjoy role playing at the gaming convention!! It sounds like great fun. And thanks for your comment about the scam I almost got sucked into. It WAS incredibly scary, especially in retrospect. It's a dangerous world, but I'm learning through experience to be cautious.
    Ann Best, Author of In the Mirror, A Memoir of Shattered Secrets

  4. I think studying movies is vital for modern authors. Literature always has to evolve to match current tastes, and cinema is the easiest way to learn what story elements are currently remaining strong.

  5. Whoa, you've got series down to a science. It makes my eye-brains spin!

    I apologize for my crazy blogpost, but I appreciate you reading the black on black. Life offline has been insane...


    Can Alex save Winter from the darkness that hunts her?

    YA Paranormal Romance, Darkspell releases October 31st!

  6. Elizabth: I've always loved learning about plot structure and how stories are crafted.

    No worries about the blog. It was a great post.

  7. As much as it may be a little emotional when we turn the last page and say goodbye to the characters we grew to love over the course of few books, still there is nothing like the anticipation of a next part just about to be published..

  8. Anna: Absolutely. I love that feeling of anticipation!