Footage of Queen to be seen for first time

Beaming with happiness, a newly engaged Princess Elizabeth cannot contain her joy, showing off the diamond ring designed by her secret fiance.

It is one of the most intimate moments of Queen Elizabeth’s life and will feature in a highly personal landmark documentary this month, telling her story ‘‘through her own eyes and in her own words’’.

The BBC team making the documentary viewed more than 400 reels of film, using the royal family’s previously unseen home movies, which have lain in the vaults of the British Film Institute for decades. Those close to the Queen say it will give her subjects a much greater understanding of her.

The 75-minute film, Elizabeth: The Unseen Queen, will include private recordings of family moments, including Philip’s first extended visit to Balmoral in the summer of 1946, when he became secretly engaged to Elizabeth, then 20. Their engagement was not publicly announced until July 1947, allowing the young couple’s romance to blossom in private.

It will be ‘‘narrated’’ by the Queen, 96, using extracts from almost 60 of her speeches between 1940 and last year, and will include speeches by George VI, Edward VIII and George V.

She has granted unfettered access to her private home movie archives for the film, which will be broadcast on BBC1 on May 29, before her jubilee celebrations in June. Documenting her as a young girl through to her Coronation in 1953 aged 27, it reveals moments from her earliest childhood, including the baby Elizabeth being pushed in a pram by her mother.

A royal source said the Queen granted access to her personal archives ‘‘to make a landmark programme that is different to what has gone before’’.