It's a simple premise pulled off superbly. Harrison Dowling's performance as the kid who doesn't want to face the monster outside, but also doesn't want to give up hope that it might be his little brother, manages to ratchet up the tension to 'holding in a fart on a first date' levels.
"I knew I shouldn't have gotten double beans with that taco platter."
But It All Falls Apart When ...
Here's how the monster behind the door ultimately gets in:
"No takesies backsies!"