The Amazing Mr Blunden

The Amazing Mr. Blunden is a 1972 family mystery and ghost film directed by Lionel Jeffries, based on the novel The Ghosts by Antonia Barber.

One day while wandering the grounds, Lucy and Jamie see two ghostly figures coming towards them a teenage girl, Sara Latimer Rosalyn Landor, and her younger brother, Georgie Marc Granger. They are two children who lived in the house a century earlier. Sara tells them that she and her brother are orphans, under the care of their dissolute and hapless Uncle Bertie James Villiers and the solicitor Mr. Blunden, until Georgie comes of age. Bertie marries a music hall performer, Bella Wickens, which Sara refers to as child like and her parents then move into Langley Park, ostensibly as the housekeeper and game keeper. The children come to suspect that Mrs. Wickens Diana Dors and her disturbed and often violent husband are plotting to kill them to get her hands on Georgies inheritance. Sara and Georgie find a book with instructions for travelling through time, so that they can get help. Lucy and Jamie agree to travel back with them they arrange to meet Sara the next day.Jamie searches the graveyard, in the hope of finding nothing and being able to go back to help, knowing in advance that they will succeed. He and Lucy are shocked and distressed to find a gravestone marked with the names of both Sara and Georgie. The sexton explains that the two children died in a fire, whose anniversary turns out to be exactly a hundred years ago tomorrow. Nevertheless, Lucy and Jamie still drink the potion and travel back to 1818 in the hope of preventing the tragedy. There they meet Thomas, the gardener Stuart Lock, who believes they are from America, and tells Lucy and Jamie that he wants to go there one day and make his fortune. Mr. Blunden is visiting the house that night, but refuses to listen to Saras pleas for help. ........

Source: Wikipedia