The adaptation of What You Need that appears on The Twilight Zone is actually quite different to the source material. The short story was quite different, and was also adapted for a television show the pre dated The Twilight Zone called Tales of Tomorrow.
If you want to do a compare and contrast you can hear a reading of the short story by yours truly
HERE.
The episode of Tales of Tomorrow is also public domain now, and you can see it
HERE. But a nice little touch on the BD of season 1 is that they've included this episode on the disks too.