Skeleton Key, along with the other Alex Rider books, is in the 3rd person limited omniscient point of view. The author focuses mostly on Alex but he also has some knowledge about the other characters thoughts. He tells of General Sarov's thoughts about his evil plan and his accomplice, Conrad. If the book was in first person it would be told by Alex. That wouldn't let us know as much about the other characters. By having a 3rd person point of view, we are able to get an unbiased description of the people Alex interacts with. It would also limit our knowledge about the secondary plot, Sarov's plan. This part is told apart from Alex's adventure until they meet, as is done in the previous books also. By keeping the villain's plan separate from Alex's story, we are able to gain more background about them and their evil plots.