The heroine ends up agreeing to become a suicide bomber, and in the process murders a double-dealing politician. "And not just my intended victim," she gloats as she picks up a carrier bag stuffed with plastic explosives. "Anyone around us would get more than they bargained for."
For this 15-year-old avenger, "We were at war. All wars carried casualties." Should parents and teachers feel concerned? Only, I would suggest, if children refuse to read the book.
Malorie Blackman was one of only two African-descended writers to feature in the BBC's Big Read selection of its viewers' 100 favourite novels. (The other, stretching a point, was the mixed-race creator of The Count of Monte Cristo, Alexandre Dumas.)
In 2001, Blackman began a series of novels about the "Noughts and Crosses": two groups, one dark and dominant (the Crosses), the other fair and oppressed (the Noughts). They co-exist, and conflict, in a fictitious segregated society that shrewdly combines elements of apartheid-era South Africa with the divided Middle East and the smouldering tensions of contemporary Britain. Both Noughts and Crosses and Knife Edge, its follow-up, sold well and won awards. Now Checkmate - the new novel - is running second in the children's sales charts to the sixth instalment of Harry Potter, while the other titles gain a second wind.
Checkmate may involve the mental preparations of a would-be bomber, but it dwells far more on redemption than destruction. At the novel's climax, the 15-year-old wannabe assassin, Callie Rose, feels while gripping her deadly burden as if "I held death in my hands. It was strange feeling. A kind of calm, deliberate disquiet."
Yet the book ends if not in happiness then at least in hope. "That's what I'm telling readers," Blackman told The Independent in a recent interview about the Noughts and Crosses series. "There is always that chance to change. Nothing is predestined."
Blackman's other episodes hardly pulled their punches either: the books detail the psychological and social havoc wrought by division and prejudice. Terrorist acts occur and in all the novels the fantasy scenario allows for an exploration of the murderous bitterness that exclusion can cause - without the straitjacket imposed by current events.
As in much of the best children's fiction, Blackman rotates the conflicts and obsessions of the contemporary world - in this case, about race, immigration and desperate youth - into a uniquely fictional dimension. She allows readers both to identify and to reflect, employing warm hearts and cool heads alike.
As so often in media stories about young people's fiction, the headline-grabbing topic only starts to make sense in a broader context. The sex, the drugs, or the graphic violence in this field may crop up with a frequency that would have shocked the guardians of children's culture even 20 years ago. But they hardly ever flourish in isolation. The finest writers for children deal in cause and consequence. They invariably show the origins and the outcome of extreme events. In contrast, plenty of "adult" genre fiction delivers merely sensations without sources.
Fiction for young readers has certainly grown tougher and bolder over the past couple of decades, breaking taboos and pushing boundaries with a courage and confidence it never had before. Setting the tone, the Potter sequence itself has darkened appreciably with each volume, as the playtime fun has faded and motifs of loss, depression and death have moved from the shadows into the heart of Harry's world. And even J K Rowling has famously run foul of American evangelical Christians, who improbably sniffed Satanism brewing in the cauldrons of Hogwarts. The merry pranks, midnight feasts and sunlit escapades that fill the Blyton-coloured memories of many older readers now seem much more than a generation away. In fact, the "golden age" of innocence in children's writing always concealed its fair share of revolt and dissent. When, in 1945, Astrid Lindgren created her much-loved nine-year-old rebel Pippi Longstocking, Sweden's leading publisher rejected this outrageous celebration of a rude, rough and disobedient girl. And in 1976, when many of the old conventions and proprieties still held in children's books, if nowhere else in publishing, Judy Blume found herself banned across America when her novel Forever spoke openly of teenage sex.
Now, more or less every taboo has been broken and every closet opened. Blackman is not the first children's author to look inside the mind of a teenage terrorist. Robert Cormier, over many years something of a byword for shock and scandal in children's fiction, did so in After the First Death as far back as 1979, with its busload of children held hostage by a despairing 16-year-old. As for racial tyranny, Beverly Naidoo helped to open many young (and older) British eyes with books such as Journey to Jo'burg, which sends a brother and sister on a harrowing trek across the benighted landscapes of apartheid South Africa.
In much the same vein, Elizabeth Laird has recently dramatised the plight of Palestinian children in the occupied West Bank in her book A Little Piece of Ground.
As for modern war and its emotional fall-out, a mushroom cloud of titles has drifted over the cultural landscape - from Robert Swindells'Brother in the Land in the 1970s and Raymond Briggs' post-nuclear comic strips in When the Wind Blows to Meg Rosoff's award-winning, top-selling How I Live Now.
And when it comes to the perils of hate-fuelled religious righteousness, Philip Pullman has written the Bible (or rather, the anti-Bible) on that with the His Dark Materials trilogy.
In this climate, Julie Burchill's lesbian romps and pashes in the (recently televised) Sugar Rush seem almost Blytonesque in their cheerful, almost wholesome adolescent lust.
So should "young adult" readers, and their older guardians or guides, become happily and totally unshockable? Probably not. Challenging material demands and deserves a vigorous response. Outrage, or excitement, need set no alarm bells ringing. But a blasé, so-what shrug should give us pause.
Melvin Burgess's teenage fiction tends to make such shrugs impossible. He can generally be relied upon to fan the flames of controversy about the limits - if any - that writers should be willing to put on the subject and style of novels for a young readership. Fresh from the storms that greeted Doing It, his sweatily authentic novel about teenage boys and their sexual lives, Burgess is about to publish Bloodsong.
This will be the second of his post-apocalyptic sagas set in a blasted capital "after the foreign planes came and nuked London flat". A thoughtful writer whose horrors are never gratuitous, Burgess has for a decade boldly gone where other children's writers seldom used to dare - ever since Junk broke the silence over drug-taking in teenage fiction in 1996.
Even so, the imminent arrival of Bloodsong may cause educators and parents a few queasy moments. It abounds in scenes such as this: "Bryony kissed him on the cheek and then pushed him, trolley and all, into the flames. The pieces of dried vegetation and paper flared up at once, then his hair, then his clothes. He began to smoke. With a section of pipe, Sigurd pushed him further into the fire where it was hotter, and he began to blaze, his skin shrivelling, his flesh hissing. The flames soon covered him. He seemed to move a little, to twist and writhe..." And so on, through a savagely dystopian novel about power, corruption and revolt that ends with "a mist of blood falling from the sky" - and even a heroine with explosives strapped around her waist.
So look forward to some bilious punditry from Disgusted of Kensington. And ignore it. Bloodsong will prove once again that it isn't the startling topics or no-holds-barred idioms that define the strongest achievements in children's fiction today.
More remarkable than the upfront passions and terrors is its ability to win and keep readers with an amazingly wide range of forms and genres - from the grittiest kinds of "dirty realism" through every possible brand of fable and fantasy. Alongside its exploits and experiments, much of mainstream adult writing looks stuck in a drearily naturalistic backwater. So read Blackman, or Pullman, or Burgess, and be shocked: not by their ambitions, but by their adult counterparts' timidity.
Not so happy ever after
By Terence Blacker
Sam comes to stay with his cousin Matthew after his mother dies but Matthew's gang is uncertain whether he can be trusted to become a member. In an initiation test which sheds some light on the divisiveness of traditional gender roles, Sam is made to dress up as a girl and spy on a rival girl gang to prove his loyalty.
By Julie Burchill
Kim, 16, is horrified when her parents' divorce means she has to leave her smart private school and go to a notorious comprehensive, Ravendene. Then she meets the gorgeous Sugar, queen of the "Ravers". Leaving her good-girl past, Kim is drawn into Sugar's daring life and falls in love with her in this story of teenage lesbianism.
By Malorie Blackman
The third in her trilogy about a ruling class of black people called Crosses and a subservient class of whites called Noughts. Callie Rose, a mixed-race teenager, whose dual heritage dooms her to a lifetime of deep-rooted prejudices, is groomed to become a suicide bomber by her Uncle Jude, the leader of a white terrorist group.
By Benjamin Zephaniah
Alem, whose father is Ethiopian and mother is Eritrean, is sent to England when his parents' respective countries go to war. He is supported by the Refugee Council and is fostered by a family but struggles to adapt to his new home, not least because he still worries about the deteriorating situation in Africa.
A LITTLE PIECE OF GROUND
By Elizabeth Laird
Set in the occupied territories in Israel, this is the story of Karim, the son of a shopkeeper, and his friends Hopper, who lives in a refugee camp, and Joni, who comes from a wealthy family. They are united in their hatred of the Israeli occupation, which offended many Jews when it was published.
HOW I LIVE NOW
By Meg Rosoff
New Yorker Daisy, 15, is sent to England to visit her aunt and four cousins. While her aunt is away on business, London is attacked and occupied by an unnamed enemy. Daisy and her cousins are forced to fend for themselves in a war which feels like a chillingly credible post-11 September catastrophe.
THE CURIOUS INCIDENT OF THE DOG IN THE NIGHT-TIME
By Mark Haddon
Christopher John Francis Boone, a mathematically gifted child, explores the secrets of his parents' failed marriage and the mystery of the neighbour's dead dog via the prism of his own autism, revealing the stresses his condition puts on his family.
By Melvin Burgess
Teenaged Gemma is bored by her life and hates her parents so she decides to run away with her boyfriend, Tar, to Bristol. They befriend two heroin addicts and become addicts themselves. They live in squats, steal and prostitute themselves to survive in a story that provoked some scandal when it won the coveted Carnegie Medal for children's books.
HIS DARK MATERIALS TRILOGY
By Philip Pullman
The story of Lyra, Pantalaimon, Will and the rest is a complicated epic about the death of God and the true nature and destiny of man. It offended some Christians who objected to its attack on religion. He creates a world where creatures called Daemons live alongside humans.
THE ILLUSTRATED MUM
By Jacqueline Wilson
Dolphin, 10, and Star, her older sister, lead an unusual life with their mother Marigold, who is covered in tattoos and is willing to do the most crazy things. She suffers from manic depressive spells and as her mental problems worsen, the girls are forced to seek outside help.