A political allegory exposes and makes an argument about a political situation through a story that features symbolic characters and events. Eugene Ionesco's play Rhinoceros seems at first glance to be an odd fantasy about people turning into rhinoceroses, but really, it is a political allegory that shows how easily people became and/or supported the Nazis.
When the first rhinoceros arrives in town, people are frightened and shocked, although one man, Berenger, is rather indifferent. His friend Jean tells him he must have more willpower and improve himself culturally in order to win the affections of Daisy. Notice how quickly people forget about the rhinoceros. Then another rhino hurries by and kills a cat. People are still shocked, but now they spend more time wondering if it was the same rhino and what breed it is. They are already getting desensitized. Something quite similar happened when the Nazi regime took control. People were shocked at first and then ignored it or discussed it without much worry about it.
As the play goes on, though, some people begin to deny the existence of the rhinos at all. It is merely "collective psychosis," one man announces. But then a rhino crashes up the stairs of Berenger's office. It is his coworker, who has changed into a rhino. Allegorically, this refers to the coworker becoming a Nazi. The coworker's wife vows to remain with him. More and more rhinos appear throughout the town as more and more townspeople transform, just like more and more people joined the Nazis as time went by.
Then Jean himself transforms into a rhino and attacks Berenger. Berenger escapes but feels guilty about Jean's transformation, thinking that if he had been more sympathetic and paid more attention, this might not have happened. He tries to drown his grief in alcohol. More and more rhinos appear, including the town's Logician, who once tried to explain the phenomenon but has now joined it. He stands for the scholars and academics who became Nazis.
Berenger's beloved, Daisy, doesn't seem to care much about the rhinos. She thinks they should just live with them and do their best to get used to them and accept them. Some people certainly thought this way about the Nazis as well. They didn't want to get involved and thought that everyone should simply tolerate each other no matter what people's viewpoints were.
Berenger, however, is determined to fight the rhinos even though Daisy thinks that they have no right to interfere with other people's lives. Daisy, however, begins to become rather attracted to the rhinos, and Berenger slaps her. Daisy leaves, and Berenger vows to fight the rhinos to the very end, symbolizing those who refused to give in to the Nazis and formed the resistance movement against them.