This is a combination of time travel and ghost story based on Lucy Boston's Green Knowe series of children's books which were published between 1954 and 1976. The film, featuring several well-known British actors including Dame Maggie Smith, went on limited British cinematic release last year and was recently shown on UK TV.
The setting is an ancient English country house at the end of World War 2. A young teenage boy, whose father has been reported missing in action, has been sent to stay with his grandmother from whom his family had been estranged. The house had been in the family for centuries and the boy explores it, fascinated by its history. He soon begins seeing visions of people from two centuries before, a few of whom (children, not adults) can also see him. He finds with increasing frequency that in going from one room to another he may suddenly be back in the 18th century, watching and listening to the people and events there. These scenes are interleaved with ones in his present day, as his grandmother (who has no problem with believing in ghosts) fills in the details of who the people were and what happened to them.
The boy becomes friends with a girl in the 18th century, a distant relative who was blind in real life but can see him. As a result he learns things which even his grandmother does not know, which are of practical benefit to the family.
This is a charming film, well-scripted and acted, and I enjoyed it throughout - but for the odd logical niggle. Now you may say that logic has no place in a ghost story, but I do like to see internal consistency. For example, the scenes set in the 18th century clearly involve the boy experiencing a kind of spiritual time travelling. He sees the house, people and events as they actually were at that time; they are not ghosts (in fact he is a kind of ghost from their future - except that he is still alive). Yet later in the story, while he is in the 20th century, he is visited by the spirit of the girl who tells him things that she could not have known while she was alive. So she really was a ghost at that point, and not time-travelling forwards to see him.
That I could just about swallow, but there was a more glaring inconsistency in the 18th century scenes, in which the boy was there in spirit only; while hardly anyone could see him (and in fact most walked straight through him) he was nonetheless able to pick up and carry material objects from that time - and leave behind physical objects he had brought with him, to be discovered a couple of centuries later. That really won't do!