Let us remember that expressionism is a branch of drama where playwrights focus on presenting a profoundly subjective view of life through the eyes of one or more of his characters. As a result of this subjective view, expressionism has been linked to strongly social concerns, as it allows a playwright to present the view of one character who is perhaps facing a situation of social injustice in one way or another. Most often, expressionistic theatre paints a rather uncompromising picture of the various faults of society. In addition, such theatre abandoned a strict chronological approach as the playwright would be able to use their imagination in focusing on one character.
When we consider this play in such terms, it is obvious that The Hairy Ape has many aspects of expressionistic theatre. It presents us with the life and perspective of Hank, and abandons a strictly chronological approach to give us a real sense of his character and the kind of dislocation and isolation he experiences. There are scenes of great imagination, such as the sections set in the stokehole. However, at the same time we can argue that this play is not purely expressionistic, as O'Neill sets off the more expressionistic elements against more conventional aspects, such as the presentation of more "normal" characters such as Long and Mildred. Such juxtaposition of course heightens the dislocation of Yank, allowing O'Neill to emphasise the expressionistic elements whilst simultaneously not creating a purely expressionistic drama.
There are some features to show expressionism in the play.the use of the language is very different. It is telegraphic. Dehumanizing aspects of 20th century is depicted with the help of inner reality because in expressionism, Surface of the reality is not so important. The idea of belonging is presented with different aspects. Therefore, people can make comment on the situation differently. With the help of these different aspects, Self-awareness can be provided.