Detective stories for 9+ have boomed in the past decade, thanks to Robin Stevens’ bestselling Murder Most Unladylike series. They’ve also evolved from Enid Blyton-style cosiness to noir lite: these are morally complex stories, in which deadly violence has a lingering emotional impact. Young readers who devour Fleur Hitchcock’s Murder at Snowfall or Sharna Jackson’s High-Rise Mystery display an appetite both for satisfying puzzles and carefully gauged realism.

Lis Jardine’s first novel is a compelling addition to the new canon. A family relocation to Bristol finds Jonno Archer resentfully enrolled at Hanbridge High; missing his friends, he decides to behave so badly that his parents reconsider the move. When he and another boy discover their PE teacher’s body in the sports shed, Jonno is initially horrified – until he realises that investigating a murder might prove top-grade misbehaviour.

Jardine’s plotting is tight, the story unspooling with satisfying speed, and Jonno’s voice is convincingly humorous and stroppy, keeping big emotions tightly under wraps. The supporting characters – geeky Daniel and ambitious school reporter Lydia – are sharply drawn, as is Jonno’s Swiss mum, with her unexpected word order. There’s the odd moment, such as a pitched battle in a hospital room, when the action feels OTT, and the footnotes teasing out Star Trek and classic crime references might be slightly overdone. But the book’s realistic grubbiness – small-scale dirty dealing, a dodgy moneylender tucked away up seedy flights of stairs – and the sense of heavy-handed authority forever looming are splendidly assured. This is a well-constructed debut, with enticing loose ends dangling to lure the reader back for book two.

• The Detention Detectives by Lis Jardine is published by Puffin (£7.99). To support the Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.