It’s often the case that a line can be drawn in an author’s body of work, past which they notably change, usually for the better: John Dickson Carr after Poison in Jest (1932), say. It is, however, rare that such a line passes through one of their works, as it does for Anthony Berkeley in Roger Sheringham and the Vane Mystery (1927). Prior to this Berkeley had written The Layton Court Mystery (1925) and The Wychford Poisoning Case (1926), which innovated in this newfangled GADisphere but seemed interesting if minor, and are not readily discussed a century later. And after it came the likes of The Poisoned Chocolates Case (1929) and Not to be Taken (1938), reprints of which were greeted with no small delight in recent years.

This third outing for Sheringham starts in the glib, frivolous manner of his early works, with Roger and his cousin Anthony Walton throwing over their holiday plans on the whim of the unpopular Mrs. Elsie Vane having gone over a cliff at Ludmouth in Hampshire. A sniff of wrong-doing attaches itself to proceedings, and so Roger and Anthony (“Must have an idiot friend with me, you know. All the best sleuths do.”) head down, encounter Inspector Moresby, and begin investigating the possible case — a case which looks so black against the dead woman’s cousin, the beautiful Margaret Cross, that Roger and the smitten Anthony almost find themselves compelled to clear her name.

Girls were weak, helpless things. Let them know they’ve got a man behind them (even a perfect stranger if the case is serious enough to warrant it) and it makes all the difference in the world to ’em. Naturally!

For a while, we go in the expected circles: some lose reasoning (“A suicide wouldn’t scream.”), the apparently-telling animosity between our suspect and our victim, a seam of self awareness (“[Roger] would hardly have dared to make use of such a situation for one of his books; it would have been voted too wildly improbable.”), and a community of various Types who all seem to have their own alibis and reasons for wanting Mrs. Vane out of the way. One feels a little sorry for Miss Williamson, the secretary to the not-exactly-mourning Dr. Vane (“She took a science degree at Cambridge – and I must say, she looks it.”), but otherwise what’s here feels comfortably familiar and very much in the slightly fatuous manner of a lot of 1920s mysteries.

This is not to dismiss Berkeley’s lively and zestful writing, however, which finds some lovely moments — a pub landlord “perspiring almost audibly”, Roger mixing two drinks “one stiff, one so stiff as to be almost rigid”, a landlady “fluttering…like a corpulent hen” — and much raillery as Anthony falls harder and harder for the comely Margaret and thus a mixture of joy and despair is felt as others are put in the frame of the “perilous position from which Margaret had been plucked”. It also slightly exposes the flaws in Berkeley’s style of mystery plotting, with nothing like the canny physical evidence that made Agatha Christie and John Dickson Carr titans in this genre, instead relying on “overwhelmingly psychological reasons” to justify many of the conclusions thrown around, as guilty parties seem to present themselves left, right, and left again.

It is in this process — in the acknowledgement that “when the known facts are so precious few, it’s possible to make half a dozen sets of deductions from them, all quite different” — that the book becomes something more than a light-hearted jape, transforming by the end into something rather more important, pointing the way to the revolution Berkeley would inspire. You feel that the author has always been on Sheringham’s side — allowing him “a piece of constructive reasoning which Roger had not the slightest hesitation in characterising in his own mind as brilliant” — and yet he sees the narrow route the genre is heading down and wishes to widen the field somewhat. “The best detectives always hold up their brilliant solutions for the more effective moment,” Roger tells us, and Berkeley turns to the camera and smirks knowingly.

And yet, for all his desire to play around with conventions, there can be no doubt that the man who would become seen as the genre’s arch innovator really does love detective fiction: all that talk of “the moral duty which every living person owes to the dead” goes very much to the heart of what is achieved here, and that appreciation of that might have got a little lost in the hare that Berkeley set racing here, to the delight of many like myself down the years. He would write more celebrated books in his esteemed career, but the quiet work done with these early Sheringhams gave so much life to the genre that it’s hard not to feel like they deserve a little more love.