Hatchett and Lycett, by Nigel Williams

Drama joins with farce, says Peter Guttridge, when the Bard of Wimbledon makes a bold move - to Croydon

Nigel Williams believes that England is its suburbs: specifically, judging by his best-known fiction, the London suburb of Wimbledon. In Hatchett and Lycett, his latest exploration of Englishness, however, he switches boroughs to Croydon in the early stages of the Second World War.

Hatchett and Lycett are friends who share a terrible childhood secret with Lycett's brother, Lucius. Their friendship falters when Lycett goes off to fight and Hatchett remains a schoolteacher alongside Norma Lewis, the woman they both love. Norma's attention is distracted by the existence of a serial killer bumping off teachers. The Spanish teacher is first to die, coming back from a school trip to France – the trip on which Norma returns with a mysterious extra schoolgirl.

Williams, in his first novel since he gave up his job as a BBC arts producer for full-time writing, has attempted to meld a love story with a war-time drama, a murder mystery and an exploration of childhood friendships and rivalries, switching always between the serious and the comic. Some comic writers go just for the laughs; the best – and they include Williams – achieve that satisfying juxtaposition of the emotionally involving with the hilarious.

In Hatchett and Lycett there are moments of brilliance – such as a boy's death on a beach – when drama abruptly elides into farce. Where the tone doesn't succeed so well is in the serial killer strand, which doesn't really engage, although an amusing nod towards Agatha Christie. Maybe Williams is more interested in character than plot, and in the childhood secret Hatchett and Lycett share. Hatchett's contradictory character is drawn with such care it is tempting to think he is Williams' embodiment of Englishness. He is clever, quick-witted and extrovert on occasion – but also, despite his sensitivity, hopeless at being himself with Norma.

The focal point is the love triangle between the central characters. But Williams doesn't seem at ease with Norma, or any of his fictional women: something of a drawback in a novel set at a girls' school.

It's an inevitable consequence of the set-up that Norma is confused almost to the end over her feelings for Hatchett and Lycett. That confusion is important for maintaining dramatic tension, but it also makes her final decision seem to come less out of her character than the requirements of the plot.

There are many things to admire. Williams wears his research lightly, although he has done a lot – about, for instance, the German atomic fission programme. There are juicy comic moments and sustained comic scenes. But there is something ultimately unsatisfying, perhaps because he tries to cram too much in. The core is the eponymous characters' childhood secret and their shared love for Norma Lewis. Everything else, while entertaining enough, remains peripheral.