Jessica has a big presentation in Palm Springs. There are a couple of problems though: her two kids who will do anything to get mom and dad back together again - even if they have to hack mom's phone or pose as a secretary to make sure dad's in Palm Springs too. And father Joe who'll do anything to charm his way back into Jessica's life.
10-year-old Finn is terrified to learn his family is relocating from sunny California to Maine in the scariest house he has ever seen! Convinced that his new house is haunted, Finn sets up a series of elaborate traps to catch the “ghost” in action. Left home alone with his sister while their parents are stranded across town, Finn’s traps catch a new target – a group of thieves who have targeted Finn’s house.
Kevin McCallister's parents have split up. Now living with his mom, he decides to spend Christmas with his dad at the mansion of his father's rich girlfriend, Natalie. Meanwhile robber Marv Merchants, one of the villains from the first two movies, partners up with a new criminal named Vera to hit Natalie's mansion.