The significance of the refrigerator light in the climax of *Wait Until Dark* is that it serves as a **crucial, mundane light source** that the sighted villain uses to momentarily **negate the blind protagonist's tactical advantage** of total darkness, and its subsequent defeat becomes the **final turning point** in the struggle for survival.
Here are the specific details:
### 1. The Villain's Counter-Tactic
* **The Set-up:** The protagonist, Susy Hendrix, is a blind woman who has plunged her entire apartment into complete darkness (by breaking all the lightbulbs, closing the blinds, and dousing the villain, Roat, with gasoline to prevent him from using matches) to "level the playing field." In the pitch black, she is an expert in her own environment, while Roat is rendered helpless.
* **Roat's Move:** The highly resourceful and sadistic villain, Harry Roat, realizes he is at a disadvantage. He opens the refrigerator door, causing its interior light to switch on automatically.
* **Significance:** This provides Roat with just enough light to see Susy and his surroundings, completely undoing her hard-won advantage and briefly terrifying her into submission. In the film, Roat props the door open, declaring, "Well, Susy, it's all over," and forcing her to give him the doll containing the heroin. The refrigerator light represents the villain's ability to find a solution in the most domestic of objects and the momentary restoration of the power dynamic in favor of the sighted.
### 2. The Final Turning Point
* **Susy's Counter-Move:** After the struggle continues, Susy is pursued by Roat in the kitchen. She manages to hide, in some versions, behind the open refrigerator door.
* **The Defeat:** In the film's terrifying final sequence, as Roat lunges at her, Susy manages to **yanks the electrical cord out of the wall**, which immediately extinguishes the refrigerator light and restores the total, absolute darkness.
* **Significance:** This final action re-establishes the absolute darkness, which is Susy's element of control, allowing her to evade the sighted killer and ultimately survive by stabbing him. The pulling of the plug is the true moment of victory for Susy, as she permanently destroys the one remaining source of light and secures her strategic advantage.
The refrigerator light is therefore a brilliant theatrical prop, transforming a common kitchen appliance into the literal hinge on which the entire climax of the suspense thriller turns.