Continuity: At the end, the enormous serial number on the helicopter changes repeatedly between shots, from G-ORMA to G-ICSG and back again.
Revealing mistakes: When Alex sets off the smoke bomb, the smoke is coming up from under the grate in the floor nowhere near the Nintendo DS.
Factual errors: The "Zit" cream that is given to Alex Rider allegedly will burn through any metal, but is harmless to a person's skin. When trapped in the aquarium with the giant Man of War jellyfish he uses the cream against the metal supports of the aquarium. This is impossible, as salt water aquariums can have no metal in them, as metal can drastically change the PH balance of the aquarium, and kill any creature in it.
Factual errors: In the rock-climbing photo the pair are each seen with a rope coiled diagonally round themselves. Although this is a common image, it is actually wrong, as there is never any reason to coil a rope like this
Errors made by characters (possibly deliberate errors by the filmmakers): Sayle says that the Portuguese Man o' War's scientific name is "Physalia physalia", but the correct name is "Physalia physalis".
Continuity: In the scene as Mrs Jones is leading Alex to Mr Blunt's office for the first time, Mrs Jones has a three inch tear visible in the back seam of the upper right arm of her jacket showing her white shirt underneath. This has then disappeared in the next scene where Alex is talking to Mr Blunt.
Factual errors: The so called Potuguese Man-of-war in the tank at Sayle's headquarters looks nothing like an actual Man-of-war. Men-of-war float on top of the water by way of a polyp filled with gas. The Man-of-war in the movie looked like a giant jellyfish.
Crew or equipment visible: At the airstrip, when Alex is sitting behind his vehicle - he's about to shoot the approaching helicopter - you can see a crew member in the reflection on the vehicle.
Errors in geography: The scene where Alex is riding through London is a never ending geographical muddle. They are seen first riding along Rotten Row, then in the opposite direction across Hyde Park Corner, then in the blink of an eye they are at the Royal Exchange, some 3 miles east.
Revealing mistakes: The scene where Alex is on the runway, before he breaks there is a birds eye view, for a few seconds you can see the skid marks that has been left from previous takes.
Crew or equipment visible: At the beginning when Alex Rider gets up to speak to the class, the microphone box is visible on his back, when they do the overhead view of the hall.
Revealing mistakes: In the opening scene, when the camera is rolling past all the class mates, one girl in the back ground quickly looks at the camera, then looks back to the front of the class again (the girl with the blue undershirt and long hair).