Holly Chase is a spoiled 16-year-old Scrooge. Raised by her father, a Hollywood director, and her stepmother, a celebrity fashionista, Holly always gets everything she wants. If she doesn't, there's hell to pay for anyone who stands in her way. After her stepmother passes away from a freak plastic surgery accident, Holly is determined to follow in her selfish footsteps and become Hollywood's leading fashion mogul. But on Christmas Eve, Holly is visited by three ghosts—the ghosts of Christmas Past, Present, and Future. They try to convince her to mend her ways before something terrible happens, but Holly chooses not to. She thinks the spontaneous and frightening visits are a load of bull.
Then, she dies.
Orphans Molly and her younger brother Kip are looking for work away from their home in famine-stricken Ireland. They find it at the Windsor estate, an isolated, sprawling house in England that is a lot more than it seems.
As they work and live with the Windsors, Molly and Kip begin to discover that the atmosphere of the old, crumbling mansion is slowly taking the life force of the once-cheerful family of four.
The last time we saw our three heroes, Anthony Lockwood, George and Lucy, they had spent a night in the most haunted house in England and conquered a feisty and persistent ghost at the bottom of the Screaming Staircase. However, six months have passed since the incident made them famous, and Lockwood & Co. are not seeing any progress toward their goal of becoming London’s (and the World’s) most successful modern-day ghost agents. To make matters worse, Fittes Agent Quill Kipps and his team of young bullies are consistently on their backs.