The main four try to help Stumpy get over his nyctophobia by plunging Smileyland into darkness so he will learn to cope with it.
"Let's Play at Playing in the Dark" contains the following tropes:
- By the Lights of Their Eyes: As most of the episode takes place in the dark, only the main four''s eyes can be seen for a large portion of the episode. Ursula and the monsters are only seen as eyes.
- Furry Reminder: Mr. Cat and Ursula can see in the dark because they're cats.
- Glass-Shattering Sound: The gang are stuck in a situation where if all the lights go out, they get attacked by monsters, so they each hold a lightbulb, flashlight or mirror to keep some sort of light with them. Unfortunately, one of the monsters grabs Stumpy's mirror, and since he Screams Like a Little Girl, everyone else's lightbulbs, mirrors, flashlights, etc. get broken.
- Here We Go Again!: At the end of the episode, Kaeloo becomes scared of the dark thanks to Mr. Cat.
- Primal Fear: Stumpy is revealed to be afraid of the dark. He gets over it by the end of the episode, but unfortunately, thanks to Mr. Cat, Kaeloo winds up becoming scared of the dark too.
- Security Cling: When Kaeloo sees the monsters for the first time, the way she moves strongly suggests that she is holding on to Mr. Cat.
