His father was the mystery/detective author Edgar Alfred Jepson (1863–1938), his mother was Frieda Holmes, daughter of the musician Henry Holmes. His sister Margaret (1907–2003; see the Times obituary ), also a novelist, was the mother of Fay Weldon.
In his SOE role, "Captain" Selwyn Jepson was recruiting officer for F section, the independent French section. As a recruiter he was one of SOE's "most skilled craftsmen" (see Foot, below), and according to (??) he was SOE's senior recruiting officer. When interviewed by the Imperial War Museum he stated:
- "I was responsible for recruiting women for the work, in the face of a good deal of opposition, I may say, from the powers that be. In my view, women were very much better than men for the work. Women, as you must know, have a far greater capacity for cool and lonely courage than men. Men usually want a mate with them. Men don't work alone, their lives tend to be always in company with other men. There was opposition from most quarters until it went up to Churchill, whom I had met before the war. He growled at me, "What are you doing?" I told him and he said, "I see you are using women to do this," and I said, "Yes, don't you think it is a very sensible thing to do?" and he said, "Yes, good luck to you." That was my authority!"
M.R.D. Foot's SOE contains an illuminating account of Jepson's interview style with potential recruits; "I have to decide whether I can risk your life and you have to decide whether you're willing to risk it" (p. 73). According to Foot, of F section's 470 agents sent into the field, 117 were killed; 39 of the 470 were women, of whom 13 failed to return.
As an aside Foot comments that captain, RN was a rank Jepson sometimes affected but to which he was not entitled ("...but the Admiralty never knew"), rather he was "a major in the Buffs" (evidently the East Kent Regiment, see e.g. ). This may or may not square with references to service in the Tanks Corps; in any case it's indicative of Jepson's personal style.
He was a well known mystery/detective author and screenwriter, best known for Keep Murder Quiet (1940), the "Eve Gill" ingénue sleuth novel series, and other non-series novels:
- The Qualified Adventurer (1922)
- Puppets of Fate (1922)
- Golden-Eyes (1922), US title The Sutton Papers
- That Fellow MacArthur (1923)
- The King's Red-Haired Girl (1923)
- Rogues and Diamonds (1925)
- Snaggletooth (1926)
- The Death Gong (1927)
- Love and Helen (1928)
- Tiger Dawn (1929)
- I Met Murder (1930)
- Rabbit's Paw (1932) US title The Mystery of the Rabbit's Paw
- Heads and Tails (1933) short story collection
- Love in Peril (1934)
- The Wise Fool (1934)
- Riviera Love Story (1948)
- Man Running (1948), as Outrun the Constable in the US. In 1950, it was published in paperback as Killer by Proxy
- Tempering Steel (1949)
- Man Dead (1951)
- The Assassin (1956)
- A Noise in the Night (1957)
- The Third Possibility (1965)
- The Angry Millionaire (1968)
- Letter to a Dead Girl (1971)
Screenwriter and director
- The Red Dress (1954) screenwriter
- The Last Moment (1954) screenwriter
- Forever My Heart (1954) screenwriter
- Sailing Along (1938) screenwriter
- Toilers of the Sea (1936) director, screenwriter
- Well Done, Henry (1936) screenwriter
- Wrath of Jealousy (1936) screenwriter
- The Scarab Murder Case (1936) screenwriter
- Kiss Me Goodbye (1935) screenwriter
- Hyde Park Corner (1935) screenwriter
- The Love Test (1935) screenwriter
- The Riverside Murder (1935) screenwriter
- Money Mad (1934) screenwriter
- For Love of You (1933) screenwriter
The Alfred Hitchcock film Stage Fright (1950) was based on Selwyn Jepson’s novel Man Running (also published as Outrun the Constable and Killer by Proxy). It was adapted for the screen by Whitfield Cook and Hitchcock’s wife and frequent collaborator Alma Reville, with additional dialog by James Bridie and Ranald MacDougall.
Selwyn Jepson had many pieces converted for broadcast by the BBC. BBC archival material exists for their productions of The Golden Dart and The Hungry Spider is held by the Mausoleum Club.