This term is known from the remarkable book by A. Mitta “Cinema between heaven and hell”. In it, the author makes an interesting observation: the plots of the overwhelming majority of world masterpieces (cinema, literature and dramaturgy) are built according to the same principles, which is a simplified form the same three-act structure.
It is well known that in every story there is a plot, development and a denouement. And this is exactly the very three-act structure. Individuality and originality will be in the mode of presentation, artistic content, but the structure in many cases will remain the same.
In his book, A. Mitta rightly believes that any drama can be built in three acts. Each act has its own goals and objectives and knowing and carrying out that, you can easily come up with a great story in a couple of hours.
1 ACT: THESIS
The main objectives of the first act are the designation of the acting forces, the description of the characters and the scene, as well as the origin of the conflict
However, at the end of the first third, there should be a sharp turn, which will complicate the situation or direct the movement of the plot in a direction unexpected for the reader. The transitional moment is very important. It is he who gives a start to the development of major events, and it is he who in many respects will determine the further interest of the public in what is happening.
The task of the first act: designation of the parties, the origin of the conflict.
2 ACT: ANTITHESIS
After a sharp turn, which completed the first act, the situation becomes more complicated. The opposing sides are moving to action: they create each other obstacles and overcome them. In the second act, a conflict develops. At the end of the second act, after a chain of complications, there is another turn that puts the parties to the conflict on the brink of disaster. This turn — the moment of maximum complication of the situation.
The task of the second act: the development of the conflict, bringing it to disaster.
3 ACT: SYNTHESIS
The hero is in danger — he makes his move, and as a result, he either wins or collapses. In any case, the conflict is at least temporarily but resolved, but the result is entirely dependent on the hero — he was able to change himself and circumstances or not.
The task of the third act: conflict resolution.
The text, planned according to the three-act structure, no longer resembles cotton wool or stretched gum, the author knows exactly what the story is leading to, but as soon as the reader begins to guess, a sharp turn occurs. But it is also interesting that the three-act can act as a universal structure, create nested constructions within itself: that is, within the framework of the first act there can be a structure of three micro-acts, revealing a local conflict. This is especially useful when working with large epic canvases.