The book is about a 14 year old boy, Alex Rider, who is puzzled by the mysterious death of his uncle Ian Rider. Alex is confused by the police office claims, “Had your uncle worn a seatbelt, he would have had a chance to survive”. Yet the boy clearly knows that his uncle was a very careful person. In the first few chapters of the book Alex have discovered little clues pointing to the malevolent death of his uncle: dozen of bullet holes on the car and a handgun which his uncle’s boss brings to the funeral. Further on Alex is invited to his uncle’s office to discuss his uncle’s will with one of the employees. Alex finds this meeting to be an appropriate time for him to carryout investigation and luckily he sneaks into his uncle’s office and starts perusing documents that might give hints about his uncle’s death. Unfortunately he is caught and shot with tranquilizer gun.
Waking up he finds himself in a very strange building and his uncle’s boss, Alan Blunt, begins to give him explanations about the current situation. Alan Blunt, spymaster for Britain’s M16 espionage agency, has blackmailed Alex and forced him to become the youngest spy in the agency. Herod Sayles, a multi-millionaire whom Alex uncle was investigating before he met his death is donating Stormbreaker (computer) to London schools for children. Alex is threatened to be sent to orphanage if he fails to undertake the mission of investigating Herod. Alex is hurriedly sent on three week training with SAS commandos and on completion is catapulted into fatal jaws of death confronting stunning collection of villains like Mr. Grin and a huge jellyfish.