Alan and Ellen have not lived the perfect life, their godparents have some unusual habits which keep them awake at night and then there's the visitors who never seem to last the night.
When Alan spies an opportunity and acts he prompts a cascade of events which will alter all of their lives and bring them into contact with an alternate reality, which is not at all happy with the current state of affairs.
Horrific, satirical and at times even political A Scary Tale could be the death of your recollection of the fanciful world of fairy tales.