In the beginning we are introduced to Mr. and Mrs. Smith sitting in their living room after dinner. Mrs Smith recounts the dull events that have taken place that day. Afterwards, the pair moves onto discussing the death of Bobby Watson, an acquaintance of theirs, who, as it seems has died recently. However, we soon learn that Bobby died four years ago. Interestingly, the Smiths mention that Bobby once dated a girl with the same name as him. Also, they seem to be particularly interested in whom will his widowed wife remarry.
In the middle of their discussion Mary, their maid, makes an appearance. She announces that the Martins are at the door. Apparently they have been standing there for quite a while, as Mary was not there to let them in and they though it horribly improper to let themselves in.
As they enter the house, the Martins realize that they have an awful lot in common, so they conclude they are married. They both are originally from Manchester, they both arrived by the same train, they live at the same address, sleep in the same bed, and they both have a daughter that goes by the name Alice. Later, we learn from Mary that in fact Mr. and Mrs. Martin cannot be husband and wife, because Mrs. Martin’s daughter has white left eye and red right eye, whereas Mr. Martin’s daughter has it the other way around.
As the two couples are engaged in a conversation, the doorbell rings, but no one is at the door. Shortly afterwards the doorbell rings the second time, but again there is no one to be seen. Eventually the doorbell rings again and the Fire Chief enters. His task is to go around the city and look for fires that could be put out, but there is no fire at the Smith house. The two couples ask the Fire Chief to tell them some stories, so he does, but none of them make any sense.
Upon everyone's horror, Mary comes and asks to tell a story. The rest of the character’s find it quite inappropriate for a maid to be so bold, but that does not stop her. Mary’s story reveals that she and the Fire Chief are lovers. Afterwards she is no longer welcome in the room, and the Fire Chief takes his leave. The Smiths and the Martins continue in a conversation until the lights fade away, but all their speeches consist of pure gibberish. After the lights are on again, we find the Smiths and the Martins still in the living room and the lines from the begging of the play are repeated.