Answer: Expressionism
Explanation: In simple words, expressionism refers to the form of art whether in respect painting or drama etc in which the artist tries to convey an emotional experience rather than expressing the perceptions of the external words.
In the given drama, the protagonist is not in jail but still fells that he is and also meets several other characters to convey an emotional message with a subjective perception.
Hence the given case depicts expressionism form of theater.