Outside The Door describes the hopelessness of a post-war soldier called Beckmann who returns from Russia to find that he has lost his wife and home, as well as his illusions and beliefs. He finds every door he comes to closed. Even the Elbe River rejects his suicide, washing him up on shore. The play ends with what can be assumed to be Beckmann's death.

The play consists of five scenes in one act. It makes use of expressionist styling and even of Brechtian techniques, such as the Verfremdungseffekt (defamiliarization effect) to disorient and engage its audience.

Prologue

The play begins with an overfed undertaker (apparently Death) with hiccups examining a body by the river Elbe, not the first one. The body does not appear to belong to a soldier, although he is wearing soldier's clothes. The undertaker makes the nihilistic claim that this death changes nothing. The Old Man (apparently God) enters, crying and explaining: His children are killing each other. Since no one believes in him anymore, he can do nothing to stop them. Disinterested, the undertaker agrees that this is very tragic indeed.

God says that Death is the new God; people believe only in death. However, God remembers a skinny, sickly death. Death explains that he has grown fat during the last century, due to all the "business" from the war, and that is the cause of his hiccups. The scene ends with Death telling God to take a rest for emotional rehabilitation.

The Dream

Beckmann awakes (after his suicidal attempt) to find himself floating in the Elbe. The river turns out to be a rather resolute motherly figure. Once she discovers that Beckmann is bent on suicide, she lashes out, patronizing him. She calls him faint-hearted and explains that she will not let him kill himself. The dream ends with him washing up on the sand.

Scene I

The Other introduces himself to Beckmann. He describes himself as the "yes-sayer". Annoyed, Beckmann tells him to leave. Thereafter, a girl turns up offering to help Beckmann, by giving him dry clothing and some warmth. She explains that she's only helping him because he's so wet and cold; later, she will admit having helped him because he looked so sad and innocent.

Scene II

Beckmann follows the girl to her house, where he finds out that her husband had been a soldier, like Beckmann. The girl laughs at Beckmann's gasmask goggles, which he continues to wear, because it allows him to see the world as grey and blurry. But, her husband comes home, on crutches. It turns out this is due to a military command of sergeant Beckmann that he lost his leg.

Beckmann attempts to go back to the Elbe for another try to die, but the Other convinces him not to. Instead he is going to visit the man, who had given the commands to him.

Scene III

The third scene marks the emotional climax of the play. Beckmann appears at his former Colonel's house, just in time for dinner. He immediately blames the Colonel, telling him that for 3 years he ate caviar while the men suffered. He tells the Colonel about his nightmare.

In that dream, a fat man (Death again) plays a Military March on a very large xylophone made from human bones. The man is running back and forth, sweating blood. The blood gives him red stripes down the side of his trousers (like that of a General in the German Army.) All the dead from throughout history are there, and Beckmann is forced to stand there among them, under a sickly, discolored moon. And they are all chanting "Beckmann! Sergeant Beckmann!"

Beckmann tells the Colonel that he has returned to hand back to the Colonel the responsibility for the eleven men lost under his command. If he were able to sleep with those thousands killed in action under his command, eleven more will not change anything for him. The Colonel finds this whole idea very strange declaring it to be a joke out of place. Beckmann ought turn to the stages with it. Beckmann fetches a bottle and some bread from the dinner table, and leaves.

Scene IV

The scene opens with a monologue from the Direktor (i.e. owner and producer of an off-off theatre) about the importance of Truth in art. Someone outspoken, new, and young should be looked for.

Beckmann arrives and expresses his ideas. The director tells him he would be better off to change his mind. Nevertheless, the director agrees to give a hearing to his odd visitor.

Beckmann gives a couplet, turning up to be a morose summary of the play up to this point, the melody taken from a popular war time song, Tapfere kleine Soldatenfrau ("brave little soldier’s wife"). To the director it is all too dark and foreboding. People in these times want something encouraging, the director says. To Beckmann, that is not Truth. The director replies: "Truth has nothing to do with art." Beckmann reproaches him, and leaves the theatre.

Once again, Beckmann takes up an argument with the Other, who gives him the idea to return to his parents. Beckmann expresses some enthusiasm for the first (and only) time in the play.

Scene V

Upon arriving at his parent's house, a woman he has never seen (Frau Kramer) answers the door. He finds out that his parents are to be found in their graves, having killed themselves during the post-war denazification. Beckmann leaves, once again eager to kill himself.

The Other follows him, and the longest dialogue of the play ensues. The nihilistic point of the play comes across during this dialog: There is always suffering in the world; one cannot do anything to change that; the world will not care if you are suffering As evidence for this, Beckmann outlines a hypothetical play:
1st Act: Grey skies. A man is suffering.
2nd Act: Grey skies. The man continues to be pained.
3rd Act: It is getting dark and it is raining.
4th Act: It is darker. The man sees a door.
5th Act: It is night, deep night, and the door is closed. The man is standing outside. Outside on the doorstep. The man is standing on a riverside, be it the Elbe, the Seine, the Volga, or the Mississippi. The man stands there crazed, frozen, hungry, and damn tired. And then there is a splash, and the ripples make neat little circles, and then the curtain drops.

The Other counters that while there is always suffering in the world, there is always hope, and there is always happiness. Dwelling on the suffering cannot accomplish anything; you can make things better by focusing on the good; as he says, "Do you fear the darkness between two lamp-posts?"

One by one, each of the characters returns to defend himself. Despite their good intentions, they cannot help. Between these visits, the dialog between Beckmann and the Other goes on. There is little change in the content of their arguments; however, both of them become increasingly desperate. Finally, after the girl and her one-legged husband have left, a desperate Beckmann begins a long monologue, at the end of which he demands an answer from the Other; who is fading away. There is no reply, and Beckman realizes he is all alone. Presumably, he has drowned himself.