The Amazing Mr. Blunden

Mrs. Allen, a war widow, accepts a caretaking post at Langley Park and moves her family from their squalid Camden Town flat. They are told they’ll care for the derelict mansion until the heirs are traced, despite rumours that the house is haunted. A mysterious solicitor, Mr Frederick Percival Blunden, explains his firm represents the arrangement.

In the solicitor's office, Lucy and Jamie notice a portrait that resembles Mr Blunden. The solicitor confirms the portrait is of a man who has been dead for a hundred years, and reveals that the present Mr Blunden is his great-grandson. The hint deepens the mystery surrounding the house and its masters.

Lucy and Jamie glimpse two ghostly figures in the grounds: Sara Latimer, a teenage girl, and her younger brother Georgie. They learn that Sara and Georgie lived in Langley Park a century earlier and are now bound to the house. The sighting confirms the place is haunted by memories as well as spirits.

Sara explains she and Georgie were orphans under the care of their dissolute Uncle Bertie and the solicitor Mr Blunden until Georgie comes of age. Bertie marries Bella Wickens, and her parents move in as housekeeper and game keeper. The kids suspect Mrs Wickens and her husband of plotting to kill them to gain Georgie's inheritance.

Sara and Georgie find a book with instructions for travelling through time, offering a chance to get help. Lucy and Jamie decide to travel back with them to aid the past. They agree to meet Sara the following day.

Jamie searches the graveyard and finds a gravestone bearing Sara and Georgie's names. The sexton explains that the two children died in a fire, whose anniversary is exactly one hundred years ago tomorrow. The discovery confirms the danger and sets up the mission to intervene.

Lucy and Jamie drink the time-travel potion and journey back to 1818 to try to avert the tragedy. They meet Thomas the gardener, who believes they are from America and dreams of making his fortune there.

That night, Mr Wickens locks the children in a room above the library and starts a fire to trap them. Jamie helps Thomas save Sara, but he cannot reach Georgie through the flames. Mr Blunden arrives and tells Jamie they will go together, and Jamie is kept safe even as Blunden bears the pain.

Jamie and Mr Blunden save Georgie as the stairs collapse; Blunden perishes in the fire while the Wickens perish as well. Jamie is sheltered from the worst of the flames, but Blunden bears the pain that Jamie would have felt. The past tragedy is averted through their sacrifice.

Lucy and Jamie return to 1918; Jamie is unconscious and Lucy struggles to tell their mother what happened. The present seems altered by the events in the past, yet the truth remains just out of reach.

Back in the present, Lucy discovers that the children’s gravestone has been replaced by a memorial for Frederick Percival Blunden, the 'Good Shepherd' who died to save the children. The house remembers him in a new, heroic light. Jamie regains consciousness and the sense of closure grows.

Mr Clutterbuck arrives with documents showing that Sara Latimer married Thomas, and that their great-grandson is the late Mr. Allen, making Jamie the rightful heir to Langley Park. The legal mystery resolves the question of who should control the estate. The family begins to grasp the true history behind the house.

A car pulls up and Mr Blunden sits inside; the greeting ‘We three kings of Orient are’ hints at one more enigmatic revelation. The family realizes they now have the answers they needed about the past, the present, and the mystery of Langley Park. The film ends on a note of resolved questions and bittersweet farewells.