What was the first twist in the plot

The five sections mark the functional structure of the classic drama. They roughly correspond to the nudes scheme (cf. Freytag) and are prototypical for the stages in a drama of the closed form. The terms can hardly be applied to dramas of the open form (e.g. station drama).
Exposure: The exposition conveys, ideally at the beginning of the drama, before the first situation-changing moment of action, the knowledge of the past and determining the present conditions and conditions on which the following conflicting action is based.
The main purpose of the exposition is to inform the audience about the constellations and fundamentals that will be developed in a conflictual manner in the subsequent drama. In its primarily informative-referential function, it requires the characters to provide information that they naturally have, but which is important for the audience to understand the plot. Accordingly, this information can be contained in the speech of the characters (e.g. salutation as 'my father' as an indication of a family relationship) or it can be given indirectly (e.g. through the symbolic value of certain gestures and objects, or through the situation itself).
The term originally comes from rhetoric, where the exposure describes the presentation of the facts before the argumentation. In the context of the drama discourse in Germany, the term appears with the correspondence from G.E. Lessing, M. Mendelssohn and F. Nicolai, although the matter has been discussed for a long time.
Aristotle demands that the action begin at the beginning, so that the exposition is responsible for conveying the basic information about personnel and constellations. In French classical music, Corneille demands that no further figures should be introduced after the first act, i.e. the disposition of the conflict should be concluded in the first act, which gives it an exposed character. Other positions provide the first act of exposure of the protagonist and present the antagonist in the second.
In the late 19th and 20th centuries, the term became more and more controversial, on the one hand because there are dramas that only explain the original starting positions in the course of the plot (e.g. Shakespeare 'The Tempest'), on the other hand because the classic form of the structure has already been largely suspended (e.g. in the one-act play or station drama).
The term is also controversial today in drama analysis because, assuming the pure function of conveying information, one can always find 'exposed' passages in the text that do not necessarily have to be at the beginning of the drama.
Increase: After the initial situation has been presented, the dramatic action is set in motion by the decisive actions of the protagonist and / or antagonist.
In the increase, the 'exciting moment' is introduced into the dramatic plot, the dramatic conflict is built up through actions by the protagonist and antagonist, or the intrigue is spun that will determine the further course of the plot. This is where the first action-changing event occurs, on which all further development is based and which is intended to excite the audience's tension.
High point / turning point, peripetia: Dramatic plot element that marks the climax of the tension curve. The dramatic conflict is in principle already decided here, since the plot is given its decisive turn.
Aristotle describes the climax of the action as 'peripetia' (= reversal, turn), the point of the action at which there is a reversal of the action, which must lead to the end. According to the classicist demand, this change takes place at the end of the third act.
Retarding moment: Delay of the catastrophe, because for a short time an untragic solution appears, which turns out to be only apparent.
The retarding moment marks a last chance to escape the outcome that was actually already decided at the turning point. In tragedy, a way out of the conflict appears that ultimately turns out to be impracticable; in comedy, a further involvement here can delay the happy outcome. The retarding moment counteracts the drop in tension after the climax and at the same time prepares the end by making other solutions seem possible.
Catastrophe: The tragic end of the drama with the death of at least one protagonist.
The disaster in tragedy corresponds to the solution in comedy. The conflicting act has come to a definite and definitive end. For the tragedy, the death of the protagonist is traditionally required after he cannot resolve the conflict in any other way. In the comedy all entanglements are cleared up. With the end all threads of action are connected and the intrigue brought to its positive or negative end. In the positive case, this can be followed by a further action, which, however, does not necessarily have to be derived from the final constellation.