Scorpia Rising, the ninth, and final, novel in the Alex Rider series, was released in March 2011. In the book, Scorpia is hired to return the Elgin Marbles to Greece. Their plan includes the laying of a false trail to Cairo, Egypt, killing Alex Rider, and blackmailing London into returning the Marbles. MI6 falls for the trap and Alex is sent to Cairo, where, unbeknownst to Alex, Scorpia is pulling the strings.
This novel starts with Zeljan Kurst, leader of Scorpia, being asked by Yannis Ariston Xenopolos, a Greek billionaire with cancer, to return the Elgin Marbles to Greece. He is promised €40 million, half in advance. MI6 has found out about the visit and try to capture him due to a mole who was given a change of identity in exchange, but Scorpia agents in the museum disguised as visitors help Kurst to escape. He assigns the mission to new Scorpia member, Abdul-Aziz Al-Rahim, known as Razim, who suggests blackmail, attempting to almost ruin the British reputation with the rest of the world. Razim is studying the issue of pain, with the aim to come up with a measurable unit of pain, naming it after himself, by torturing all kinds of members of society, with a teenager being the top of his wish list, as he explains when torturing a French agent. The plan requires Scorpia to build up a file, codenamed Horseman, on the subject of Alex being used as a spy by the British government for a disgraceful act, and killed, threatening to expose it, hence ruining the British reputation, unless the Elgin Marbles are returned to Greece
In a secret prison in Gibraltar for people who are against Britain, Scorpia manages to free Julius Grief, one of Hugo Grief's clones from Point Blanc who is also Alex's look-alike. Julius is hellbent on revenge over Alex for what he did in Point Blanc. They hide a gun in the library for Julius along with instructions, enabling him to get out of the gates by taking his pyschiatrist hostage. His death is faked with a remote-controlled car, a duplicate of the one he was driving which contains a dummy in the front, being sent over a cliff which is released from a barn soon after he drives into it. Scorpia also decides that the best way to start the ball rolling would be for a body leading MI6 to Cairo, where the main action will happen, to be found, and Kurst decides this is another Scorpia board member Levi Kroll, who opposed the plan initially, and is shot in the neck by a sniper. In Britain, MI6 scientists find Kroll, who was found floating in the River Thames, to suspect an attack at the Cairo International College of Arts and Education in Cairo, Egypt, where many wealthy children are sent.
At Alex's school, Alex's school is attacked by a sniper who wounds his friend Tom Harris in the arm with his second shot. Alex follows the sniper and is able to send the helicopter and the sniper who is escaping in crashing into the Thames. This gives Alan Blunt a chance to send Alex on a mission to Cairo to investigate the new head of security Erik Gunter, believing he might have somethings to do with Scorpia. Unlike in most other missions, Alex's friend and guardian Jack Starbright demands to come along to keep an eye on him, as well as Derek Smithers being sent from MI6 to co-ordinate the mission. The action ultimately leads Alex to a floating market, the House of Gold, where Gunter has shot a weapons dealer after he sells him a gun, whose body Alex finds. The market is blown up whilst he is on it. He is then kidnapped by a mysterious group, who take him to a room where he is waterboarded for information. However, this is quickly stopped by Joe Byrne, revealing that the mysterious group are the CIA, who have recognized Alex as an MI6 spy and believe he is there as an assassin. Byrne explains that they are in Cairo to protect the American Secretary of State, who is planning to make a speech announcing Britain to be less influential as a world power – they are well aware of the furore that will be caused by the speech (mentioning that even the President tried to stop it) and, though not happy, are forced to provide security.
Scorpia then begins to target Smithers, who is found to have booby trapped his entire house in Cairo, from itching powder to a doormat which leads to the Cairo sewers. Alex then finds out what Smithers' last gadget is - a fat suit which he has been wearing since the moment Alex met him - and discovers that Smithers is really a skinny Irishman in his late thirties. He says they should split up, and leaves. Alex gets home, but finds Jack has been kidnapped and a note is ordering him to get to a certain location, or she will die. Both Alex and Jack are taken to Razim's fort in the Sahara Desert, where Alex is taken to be Razim's next subject. However, for the plan to work out, they cannot physically cause him pain or mark his body in any way. So Razim instead decides to use the opportunity to subject him to emotional pain. To do this, he strips Alex down to his boxers, ties him up, and attaches several emotion-recording devices to him. Razim pretends to allow Jack to escape from her cell by making sure one of the bars is weak enough to be removed with a knife Jack has stolen, knock out a guard and drive off in an old Land Rover. Unbeknownst to her, the Land Rover has 30 kilograms of explosives connected to it and, with Alex watching live on a screen, Julius detonates the bomb, killing her instantly. Alex's grief is too much for him to handle and he blacks out.
Alex is bound and gagged, then taken to Cairo, where he is told what will face him by Gunter – when the American Secretary of State decries the United Kingdom and gives her anti-British speech, Julius (posing as Alex) will assassinate her, and in the clamor that follows, Alex's body will be found nearby.This dives coherent explanation, that Alex killed her. Days later, Scorpia will begin their blackmail, threatening to expose their file on MI6's use of a schoolboy as an assassin unless the Elgin Marbles are returned. As a last request, Alex asks for a cigarette, and as Gunter opens the packet, an irate scorpion inside the packet stings him. This immobilises Gunter enough for Alex to steal his gun and break his nose, killing him from the trauma. Alex then rushes inside, just at the time when Julius was sneaking away in order to go to his hidden sniper rifle and kill the Secretary of State. However, Alex distracts Julius just in the nick of time, so a shot is fired, alerting everyone to the presence of a sniper, but no one is killed. This organises the frenzy required, but Julius slips away into the crowd, leaving Alex to need to give chase or lose him again.
Alex chases Julius through the streets of Cairo, culminating in a grassy verge by the side of a road, where Julius is hit by a car. He claims that Alex wouldn't dare kill him, but as Alex turns away, Julius goes for his gun, and is shot in turn by Alex. This is the first time Alex has ever shot someone. He then meets up with the CIA, who are forming a joint taskforce with the Egyptians in order to take out Razim in the desert. However, they need Alex to come with them to be able to properly locate him, and so as to avoid suspicion when landing. They torture the pilot in order out the code word (Selket) so they won't get shot down while approaching the fort, which works out, and Alex poses as Julius when arriving. However, Razim sees through this, and a shootout begins, eventually ending on the drawbridge between the two halves of the fort, where Razim falls off when it splits, and falls into the salt pile below where he is slowly crushed to death. After this incident, the remaining Scorpia members are arrested including Kurst. Back in England, Blunt is retiring and will leave his job to Mrs. Jones. Before Blunt says goodbye, Mrs. Jones reveals that she knows Blunt hired the sniper to fire at Alex's school, which means that he also is responsible for Jack's death. Alex is adopted by Edward Pleasure, Sabina Pleasure's father, who is confident Alex will get better with his family.