On a bright July Monday in 1895, Robert Coombes, 13, and his 12-year-old brother, Nathaniel, called Nattie, set off from their East London home to see a cricket match. Before leaving, they gave a neighbor money to pay the rent when the landlord arrived. Their father, a ship’s chief steward, had recently set out to sea, and their mother, Robert explained, was going to visit an aunt in Liverpool.  Or was she? As the days passed, Robert, whose schooling had ended and who had recently quit a job in the shipyards, and Nattie, playing hooky, continued to enjoy themselves, going once again to the cricket match and later to the theater. They fetched an old family friend, the somewhat dimwitted but amiable John Fox, from the ship he worked on and moved him into the house to act as caretaker — and to pawn the boys’ watches, so that they remained in funds.  But friends and relations of their mother, Emily, soon began asking pointed questions about her absence. A neighbor noticed a foul smell emanating from the house.  Any reader can probably guess where this is going. But it’s a testament to the tension-stoking skills of Kate Summerscale, author of “The Wicked Boy,” that our prickly suspicion that Emily Coombes is not visiting an aunt in Liverpool does not detract from our swift immersion in the narrative. In fact, the first pages of the book are among its most gripping.  When the door to Emily’s bedroom is finally breached, the scene revealed is gruesome. Maggots had consumed much of her flesh, although a coroner was able to determine the cause of death: two stab wounds. Scotland Yard did not have to look far for a suspect: Immediately after the body was discovered, Robert calmly explained that he had killed his mother, ostensibly because she had beaten Nattie for stealing some food, and threatened to beat him, too. But if this were a crime of impulse, why did Robert buy the knife he used days earlier?  Ms. Summerscale has found a nifty literary specialty: resurrecting and reanimating, in detail as much forensic as it is novelistic, notorious true-life tales of the Victorian era. In “The Suspicions of Mr. Whicher,” she wrote about another infamous murder, in 1860, and the Scotland Yard detective who solved it but was unable to prove his case — to the lasting damage of a storied career. In “Mrs. Robinson’s Disgrace,” she investigated one of the most scandalous divorce cases of the era.  “The Wicked Boy” explores the aftermath of Robert’s sensational confession as it reverberates through the culture. Tabloids reveled in lurid accounts, and there were hand-wringing editorials from the more sober papers about the evil influence of the penny dreadfuls, the cheap magazines full of tales of adventure and gore that were the steady reading diet of boys like Robert. Initially Robert, Nattie and Fox are all charged with murder. Later the charges against Nattie are dropped — although it was clear he knew what Robert planned to do — in part so he could testify against his brother.  Enjoyable as an atmospheric tale of crime and punishment from a distant era written in lucid, limber prose, “The Wicked Boy” also implicitly raises questions that remain with us today. Are children who kill to be treated as beings fully cognizant of the moral iniquity of their behavior, and held responsible for it? Does an act as heinous as the one Robert committed automatically imply mental illness? Do violent video games have a pernicious influence on contemporary children akin to the suggested impact of the bloody penny dreadfuls on Robert?  These and other pertinent issues are not foregrounded. Ms. Summerscale’s easy mastery of what turns out to be a complicated, at times surprising narrative drives the book forward. The crime and the trial, while described in probing detail — Robert’s odd, laughing demeanor in the courtroom dock strikes a particularly chilling note — unexpectedly take up only about half the book.  Ms. Summerscale then takes us inside Broadmoor, England’s most famous criminal psychiatric hospital — or, as it was then more bluntly called, lunatic asylum. It was here that Robert was ultimately sent, after a jury, at the nudging of a somewhat domineering judge, declared Robert “guilty but insane.” (The jury had found him guilty but recommended “mercy on the ground of his youth”; the judge insisted he be found guilty or guilty but insane.)  The pages devoted to Robert’s life inside Broadmoor are full of peculiar detail about both the inhabitants and their wardens. How’s this for a sentence almost as funny as it is macabre: “In the summer months,” we’re told, Robert “played cricket for the Block 2 team, as did Alfred Gamble, the costermonger’s boy who had attacked young children, Arthur Gilbert Cooper, the curate who had cut his vicar’s throat, and Roderick Maclean, the would-be royal assassin and aspiring poet.” Must have been quite a game.  And there are more strange twists in the tale ahead. Robert is eventually released and moves to Australia, where he joins the army when World War I breaks out; he becomes a band leader (he was always musically gifted) and stretcher-bearer, and earns medals for his courage and cool under fire.  How to square the grown man, a wartime hero who later informally adopted a neighbor’s child when he saw he was being abused, with the boy who could so violently murder his mother, then go larking off to a cricket match? (Perhaps that coolness provides a clue.) Ms. Summerscale draws no firm psychological conclusions, but instead leaves the mystery of the boy and the man to our imaginations, where it pricks at us throughout the book.  The Mystery of a Victorian Child Murderer  Illustrated. 378 pages. Penguin Press. $28.00.  A version of this review appears in print on July 26, 2016, on page C4 of the New York edition with the headline: A Boy Murders Mum, Then Fun and Games. Today's Paper|Subscribe
Kate Summerscale resurrects a notorious true-life tale of murder in the Victorian era committed by a 13-year-old boy.