Lord Brabourne, producer of such films as Murder on the Orient Express, Death on the Nile and A Passage to India, has died at the age of 80.
Lord Brabourne's film credits include Murder on the Orient Express
He passed away peacefully at his Kent home with his wife Countess Mountbatten of Burma and their six children at his side, according to a spokeswoman.
Lord Brabourne began his film career as production manager on such movies as 1956's The Battle of the River Plate.
His other films as producer include Sink the Bismarck! and Little Dorrit.
As son-in-law of Lord Mountbatten, the Queen's cousin, he was able to use his family connections to obtain Royal Navy assistance for some of his productions.
In the 1960s he produced two celebrated Shakespeare adaptations: the 1965 film of Othello starring Laurence Olivier and Franco Zeffirelli's 1968 Romeo and Juliet.
The latter received an Academy Award nomination for best picture, as did A Passage to India in 1985.
Sir Peter Ustinov played Hercule Poirot in 1978's Death on the Nile
A director of Thames Television, Euston Films and Thorn EMI, he was made a fellow of the British Film Institute in 1979.
Born John Ulick Knatchbull in 1924, the seventh Baron Brabourne married Patricia Mountbatten in 1946 and they had seven children.
The baron was among the seven-strong boat party which was blown up by the IRA at County Sligo, Republic of Ireland, in 1979.
His 14-year-old son Nicholas and mother the Dowager Lady Brabourne were killed alongside his father-in-law Lord Mountbatten.
Lord Brabourne, his wife and Nicholas' twin brother Timothy survived after being thrown clear, but suffered serious injuries.
A local boat boy, Paul Maxwell, also died and the survivors all suffered serious injuries in the explosion on Lord Mountbatten's boat.