It’s Halloween night, and the thing that most terrifies teenage misfit Kelly Ferguson (Tamara Smart) is making it through the popular kids’ party without being called “Monster Girl.” After the ill-advised choice to tell her peers about a traumatic incident of almost getting snatched by a monster as a child, the unfortunate nickname has stuck and tanked all hope of ever joining the in-crowd. It’s useful, then, that her mother (Crystal Balint) promised Kelly’s babysitting services to her ice queen boss Ms. Zellman (Tamsen McDonough) and her problem child Jacob (Ian Ho). But when that adorable child gets snatched by the same otherworldly creature that once haunted Kelly, the hapless caretaker is thrown into a secret underworld and gets her first lesson in A Babysitter’s Guide to Monster Hunting.