Guest Stars Tess Atkins as Sydney Jared Gertner as Len Fletcher Co Starring Yasmeene Ball as Teenage Amara Claude Knowlton as Detective Madsen Finn Wolfhard as Jordie Pinsky Glynis Davies as Mrs. Kemper Emily Haine as Wendy Tracey Power as Dawn Pinsky David Lennon as Wendy's Boyfriend Thomas Jones as Mason Kemper