Alex Rider is a series of spy novels by the English author Anthony Horowitz. The novels revolve around the teenaged spy Alex Rider and are primarily aimed towards young adults. The series comprises 14 novels, as well as seven graphic novels, seven short stories, and a supplementary book.

The first novel, Stormbreaker, was released in the United Kingdom in 2000 and was adapted into a film in 2006, starring Alex Pettyfer as the titular protagonist. The books Point Blanc, Eagle Strike, and Scorpia books were adapted into a TV series in 2020, 2021, and 2024, respectively, starring Otto Farrant. Walker Books published the first novels in the United Kingdom alongside Puffin in the United States. More recent entries in the series were published by Philomel Books, an imprint of Penguin Books.

Stormbreaker was published in 2000, in the United Kingdom, and then in 2001 in the United States. Alex, the main character, is recruited by MI6 after discovering the truth about his uncle's life and death. He is sent to complete his uncle's latest mission: to investigate the Lebanese multimillionaire Herod Sayle and his creation: the revolutionary and newly developed computer called Stormbreaker – which Sayle is donating to every school in England. Alex discovers that the Stormbreaker computers contain a lethal variation of smallpox and that Sayle plans to kill thousands of schoolchildren around the country with it. Alex foils the plan and succeeds on his first mission.

Point Blanc was published in the United Kingdom in 2001, and in North America in 2002 under the alternative title Point Blank. After the deaths of two billionaires, MI6 discovers a connection: the two men who died each had a son attending Point Blanc, a school for rebellious sons of billionaires located in the French Alps, owned by Dr. Hugo Grief. MI6 sends Alex to investigate Point Blanc, where he discovers that Grief is replacing the students with clones of himself, who are altered through plastic surgery to resemble the students, including Alex himself, so Grief can inherit the fortune and gain the power to control the whole world. However, Alex foils his plan and is given a second sick note by MI6. The book was adapted as the basis for the first series of the Alex Rider television series.

Skeleton Key was published in 2002. After foiling a Triad plot to fix the 2001 Wimbledon tennis tournament and befriending Sabina, Alex is in grave danger of assassination. Forced to leave the country, MI6 sends him on a mission to Cuba with two doubtful CIA agents, of whom he is the sole survivor. He encounters former Soviet general Alexei Sarov, who tries to adopt Alex and expresses ideas of a nuclear holocaust and world domination under communist rule. Alex then foils his plans, saving the world for a third time.

Eagle Strike was published in 2003. Popstar Damian Cray hopes to destroy the drug-making countries of the world by hijacking the United States nuclear arsenal. Suspicious of him, Alex takes Cray on without the help of the sceptical MI6. Cray releases a state-of-the-art games console called the 'Gameslayer', with its first game, 'Feathered Serpent', being much more than it seems. Alex uncovers a plot involving the US government and the international community but is caught spying and forced into a real-life version of 'Feathered Serpent' which he manages to escape by cheating. He leaves Damian Cray's mansion after stealing a piece of equipment vital to Damian's plan but is forced to give it up because Damian kidnaps Alex's girlfriend, Sabina. The two enter Air Force One, where Damian Cray launches nuclear missiles at the drug-supplying countries. Cray kills Yassen Gregorovich, but soon after Alex pushes Cray to his death. He then stops the missiles before they can hit their targets. Just before dying, Gregorovich tells Alex to look for a criminal organization called Scorpia, a group he claims Alex's father worked for. The book was adapted as the basis for the second series of the Alex Rider television series.

Scorpia was published in 2004. Following the advice of the assassin Yassen Gregorovich, Alex seeks the criminal organization Scorpia to find the truth about his father. He is soon recruited by Scorpia executive Julia Rothman, and he is trained as an assassin before being ordered to kill Mrs. Jones. He fails in this mission but realigns with MI6 after learning that thousands of schoolchildren in London would die if he did not help them. Alex is returned to Scorpia as a double agent and discovers the broadcasting dishes that Scorpia intends to use to kill their targets, including Alex, as he was injected at their training school in Malagosto, which are later lifted into the sky by a hot air balloon. Rothman's henchman, Nile, tries to stop Alex, but he is afraid of heights, causing him to slip and fall to his death after being taunted by Alex. Alex manages to stop the death of the schoolchildren while Rothman herself is killed when the dish equipment falls on top of her. At the end of the novel, Mrs. Jones and Alan Blunt tell Alex the truth about his father; he was an MI6 agent working as a double agent in Scorpia attempting to take down the organization. They also explain his parents' death, ordered by Julia Rothman after she was notified of his father's treachery along with the true details of the event that happened on Albert Bridge. As Alex leaves Liverpool Street, a Scorpia sniper shoots him. The book was adapted as the basis for the third series of the Alex Rider television series.

Ark Angel, published in 2005, follows Alex's second mission for the CIA. After recovering from a Scorpia assassination attempt, he is sent to investigate businessman Nikolei Drevin, who built a hotel in outer space called "Ark Angel." The hotel was ultimately left unfinished due to high expenses. After Alex's cover is blown, Drevin learns that the CIA is gathering evidence against him and plans to retaliate by attacking the Pentagon. Drevin is killed and Alex is sent into space, moving the bomb to prevent the wreckage from entering the atmosphere.