The death at the heart of JK Rowling's second crime novel is worthy of the generation weaned on the savagery of Game Of Thrones.

As her private eye Cormoran Strike reflects, "this murder was elaborate, strange, sadistic and grotesque, literary in inspiration and ruthless in execution".

The dead man is novelist Owen Quine, the sort who flounces around in a Tyrolean cape and feathered hat, as if he has escaped from Rembrandt's The Nightwatch to modern London. Or at least, London a few years ago, when the News Of The World was in its phone-tapping prime. Rowling, under the name of Robert Galbraith, cannot resist taking a swipe at his/her tabloid tormentors, and the opening chapter's depiction of the greedy journalist desperate for dirt, a scene irrelevant to the rest of the plot, is revenge of a sort.

What follows, however, is retribution of another order. Since each chapter is prefaced by a quote from writers such as Ben Jonson or John Webster, it is no surprise when it becomes clear that Jacobean melodrama and tragedy is the spindle on which this far-fetched yarn is spun.

Cormoran Strike, named after a Cornish giant, is to the detective world what Hagrid was to Hogwarts. An enormous fellow - six foot three, size 14 shoes, and arms that Galbraith constantly reminds us are large and hairy - he is a comforting, protective presence, partly for his size, but more because of his kindly personality. Filling the reader in on his background - the illegitimate son of a rock star, "no more than a famous singer's zygote" - he is a decorated war veteran, who lost part of his leg in Afghanistan, and is trying to make a living as an investigator, with the help of his delectable sidekick Robin.

Approached by a shilpit-looking Mrs Quine to investigate her husband's disappearance, Strike finds himself entering the febrile world of publishing, a snake-pit Galbraith portrays with relish. There are many things awry with this novel, not least its lack of style, but Galbraith cannot be accused of under-egging his/her characters. From the pert, posh girls found in every publishing house, to the dragon of an agent who, as a nicotine addict, literally breathes smoke, and a cartoonish assortment of pompous authors, sensitive editors and wannabe writers, he/she draws a recognisable caricature of what Muriel Spark dubbed "the world of books".

Filled with so many red herrings he/she must have breached an EU quota, The Silkworm is an uneven and rather cruel piece of work, an unsettling mix of the cosily old-fashioned and the morbid. Unable to allow the story to tell itself, Galbraith micromanages every step the characters take. No meal is omitted, no reminder of their appearance left unsaid. We repeatedly watch Strike strap on his prosthesis, the point about his disability, and its complicated legacy, hammered home ceaselessly, as is the decrepitude of his flat, his ill-fitting windows drawing Galbraith's attention every time he returns home. Even toilet breaks are listed, lest readers find themselves cross-legged with anxiety. Meanwhile, the cityscape of London is offered up in A-Z manner, Galbraith indicating tube lines taken and taxi routes followed, and commenting on sites of interest as he/she goes.

In this Galbraith is in the company of many crime writers, the book at times feeling less like a novel and more like direction for a TV drama. One thing is certain, however: it does not lack drama. Quite apart from the sick murder plot, there is Strike's former fiancee's impending marriage and sidekick Robin's approaching nuptials to a man Strike considers a "d***head".

The Silkworm is an homage to the Jacobeans, but in the manner of the New Elizabethans. Combining the mundane with the seedily macabre, Galbraith creates an overheated, at times childishly overwritten, concoction. When even a humble fish becomes a source of danger - "he was attempting to prise spines out of the Dover sole he had recklessly asked to be left on the bone" - one has to wonder why one needs ghoulishly improbable murder for a thrill.