He is chiefly remembered for his liaison in 1929 with Evelyn Gardner while she was married to Evelyn Waugh. He is portrayed as "John Beaver" in Waugh's A Handful of Dust and as "Sir Piers Tofield" in Henry Williamson's Chronicle of Ancient Sunlight.
He was educated at Eton College and graduated from Balliol College, Oxford with a Bachelor of Arts degree. In 1926 he went to Heidelberg as a trainee for the Foreign Office. He subsequently got a job as an assistant news editor at the BBC.
In the late 1920s Heygate was on the fringes of the group of socialites known as the "Bright Young People" and was friends with the author Anthony Powell. In 1929 divorce proceedings began between Evelyn Waugh and the Honourable Evelyn Gardner (a daughter of the 1st Baron Burghclere). Heygate was cited and hence was forced to resign from the BBC. (This scandal is said to be one reason why the BBC's first Director General, Reith, took a firm line against any of his staff being involved in a divorce). In 1930 he married Gardner.
In 1932 he joined the Gaumont-British Picture Corporation and worked in collaboration with the German UFA film company at their Babelsberg Studio near Berlin. Of staunch right-wing views, he was present at the 1935 Nuremberg Rally in the company of his friend the writer Henry Williamson. In neighbouring seats were Unity Mitford, Diana Mitford and Dr. Frank Buchman
Heygate and Evelyn were divorced in 1936. In February of the same year, he remarried, to the Gaumont-British actress Gwyneth Lloyd (of the Lloyd's Bank family). They subsequently moved to Sussex. They had two sons George and Richard, both of whom eventually inherited the baronetcy.
He succeeded to the title of 4th Baronet Heygate, of Southend, Essex on 14 January 1940.
In 1976 Heygate committed suicide by shooting himself. He was 72.
His books comprise:
- Decent Fellows (1930), a public school novel.
- White Angel (1934)
- Talking Picture (Jonathan Cape, 1934), a semi-autobiographical novel dealing with experiences in Weimar Berlin, similar to Christopher Isherwood's I Am a Camera.
- Motor Tramp (Jonathan Cape, 1935), a factual account of tours in an MG motor car, including a visit to Nazi Germany.
- A House for Joanna (1937). A tale of life on the Sussex coast.
- These Germans: An estimate of their character seen in flashes from the drama, 1918–1939 (1940)
- Love and Death (1943)
- Kurumba (Eyre & Spottiswoode, 1949). Described as: A raffish, intelligent tale of a soldier and his native mistress, set in the imaginary Kurumba, somewhere on the Indian sub-continent, during the second world war.
- The Only Girl (Ich und die Kaiserin) (1934)
- Black Roses (Schwarze Rosen) (1935)
- What to read when you're... tempted by infidelity, Justine Picardie, The Daily Telegraph 3 October 2008
- I am also a camera: John Heygate and Talking Picture Geoff Brown, Film History, vol 20, 2008
- The life of Evelyn Waugh: a critical biography, Douglas Lane Patey, 1998
- Evelyn Waugh, A. P. Herbert and Divorce Reform, Tony Lurcock, Evelyn Waugh Newsletter And Studies, Vol. 35, No. 2, Autumn 2004
- Unity Mitford: an enquiry into her life and the frivolity of evil, p. 121. David Pryce-Jones 1977
- Obituary: Gwyneth Lloyd Richard Heygate and Alison Donaldson The Independent 13 May 1994
- Biographies, Bart and Bounder.com
- The Peerage
- Exhibitions Irish Arts Review (1984–1987), Vol. 1, No. 2 (Summer, 1984), p. 55]
- Obituary: Evelyn Nightingale, Marie-Jaqueline Lancaster, The Independent, 5 April 1994
- MG Motor Tramp, David Landers, Classic Motor Monthly, February 1995
- Book details, A House for Joanna Church Street Books, AbeBooks
- Book details, Kurumba, Charles Cox Rare Books, AbeBooks
- Internet Movie Database