Jackie Rhoades, a cheap nervous petty crook, is sweltering in his hotel room when he gets a call from George, a local crook, who wants Jackie to do something special for him. Jackie tries to get an answer but quickly backs down and hangs up. A few minutes later George arrives and regards Jackie with contempt, then asks what kind of job he wants to do. Jackie admits that the last few jobs have been rough, and he'd rather stick to bunco and shakedowns. George explains that tonight Jackie is going to become a man and gives him a gun. He tells Jackie that he needs to knock off an old man who runs a local bar who's refusing to pay protection money. Jackie doesn't think he can handle it but when he tries to back out, George slaps him and tells Jackie that he's in hock to him and that if he doesn't do it, George will finish him off. The old man closes at 2 so Jackie is to kill him and then meet George back at the hotel at 2:30.
After George leaves, Jackie paces around the room and considers the fix he's in. He bites his nails nervously and swings back and forth between whining about his lousy life and deciding he's going to become a killer. Finally he looks at himself in the mirror and admits he'll probably get caught and serve hard time, but if he doesn't go through with it he'll get killed. He takes out a cigarette and looks for a light.. and his mirror image lights a cigarette and blows smoke at him. Jackie backs away but his mirror image, confident and self-assured, tells him to stay put. Jackie wonders if he's going insane but his mirror image, "John," tells him that if Jackie dies then he dies too. Jackie once had a choice, and could have become a man or a mouse. Jackie went one way, and John ended up as nothing but a reflection. Jackie tries to leave but everywhere he goes he runs up against a mirror with John in it, telling him he's got no way to escape. Finally Jackie collapses on the bed and passes out.
Jackie wakes up to find himself face-to-face with the gun on the nightstand. He prepares to leave on the job but John is still there and says that if Jackie ruins his own life, he'll ruin John's as well. They both know that Jackie will never get away with killing the old man. Jackie tries to explain, saying he was a runt and had to join a street gang. John's heard it all before and says that Jackie had his chances: a sympathetic parole officer, a beautiful girl that gave up on Jackie after he served a two-year stretch in prison. Jackie says he doesn't need dames but John knows better, saying he wouldn't know what to do with a caring woman. But John does, and he wants his chance at a decent life.
George calls to tell Jackie that it's almost 2. Jackie prepares to head out and discovers that his reflection has disappeared entirely from the wardrobe mirror. He tries to find it, pulling the wardrobe away from the wall. There's nothing there and he angrily spins the mirror... then looks on in horror as John appears, getting larger.
It's 2:30 and George storms into the room, demanding to know why Jackie didn't go through with the murder. Jackie is sitting quietly, his hands in his face. George prepares to kill him... and it's John that looks up. He tells George that he's resigning, then beats the crook up and knocks him to the ground. John grabs the door and shoves George out, and tells him never to show up again. He then calls down to the desk to inform him that he's checking out of the lousy hotel. As he prepares to leave, he looks at the mirror and sees a nervous Jackie, biting his nails and wondering what "they" are going to do next. John informs him that it's time to get a job and maybe find a woman to marry... and stop biting their nails.