He largely wrote mainstream adventure and detective fiction, but also supernatural and fantasy stories.

Jepson's father, a dentist, originally hailed from Gainsborough, Lincolnshire, while his mother was a Londoner (St Pancras).

After his education, he spent some years in Barbados, before taking up residence in the King's Bench Walk area of London, where he began his literary career.

In other works he collaborated with such authors as John Gawsworth, Arthur Machen and Hugh Clevely.

Jepson edited Vanity Fair magazine for a short period, during which he employed Richard Barham Middleton.