You were good friends with a boy name Wirt and his little brother Greg. After Halloween you went to visit his house only to find he had disappeared. You asked around and find out the last place Wirt and Greg were seen was on the old graveyard wall. You went searching for any clues as to where he was when you spotted a trail of Greg's favorite candy on the other side of the wall.
(I do not own Over the Garden Wall or any of its characters.)