|“||In half an hour, the Old Ones will be here and everything will be ours!||„|
|~ Fabian to Rodriguez|
Fabian is a character in the The Power of Five books and is not originally a villain, but as the series progresses he becomes revealed as the traitor in the Nexus organization and one of the main reasons for all of Matt's misfortunes. He was originally fighting the Old Ones but then he decided to join them. He ends up being the tertiary antagonist of book two, Evil Star.
Fabian first appeared in Raven's Gate in the very last chapter like a swan and started to doubt Richard's story about the Old Ones but he eventually gave in and said that he believed his story and he was part of the Nexus "if it was known I was part of the Nexus, I would have to resign" but then he told Matt of another dimensional gate opening in Peru sometime soon, but he didn't know where it was or what it looked like. He asked Matt if he could help the Nexus again but Matt wanted to be left alone. So, Fabian gave Matt and Richard some money to live on and did leave them.
But he returned in Evil Star, playing a bigger role, where he came with the medium Susan Ashwood to Richard's and told them about the gate. When Susan first asked Matt to help them again, he refused, and said he'd had enough of being out of control and wanted quiet. Fabian got angry and said it was only because of him and Susan that Matt and Richard had a good life and Fabian threatened "maybe we should think again" but he was reprimanded by Susan who said of course Matt could disagree he had a right but she warned him that soon he may have less choice than he thought.
Fabian and Susan reappeared few days later and Fabian showed Richard a film of a man who had found the diary of Saint Joseph. The man, William Morton, had been in contact with the Nexus. Fabian asked Matt if he could meet Morton to show he was a Gatekeeper and to get the diary which could show them where the gate was and how to stop the Old Ones. But Matt refused. However, after much thought - coupled with his evil aunt almost killing him and blowing up his school - Matt went back to the Nexus and said he would meet with Morton. Matt found Morton mad, but obeyed his command to go through a small door with a pentagram on it in the church and bring back something from behind. However, Fabian, being a traitor, had intercepted the meeting with Morton and told Salamanda about it, Salamanda had sent in an assassin, and the man killed Morton, but Matt wasn't there so he escaped.
When Matt did go to Peru, Fabian betrayed Matt by having the police at the hotel instead of Fabian. Fabian let the police beat up Matt. Then when Matt phoned Fabian in the capital Fabian phoned Salamander and said that he could go after Matt. Matt was once again almost killed.
When Matt and Incas broke into Salamanda's house, Matt and Richard went to stop the gate being opened. Salamanda was using a satellite to unlock the gate and they hoped they could blow up the satellite or send it off into space. However, they met Fabian.
Fabian admitted to being a traitor to the Nexus, saying Salamanda was his publisher, and that the Old Ones were too strong to fight. Also he said he'd be rewarded for his loyalty to the Old Ones. Salamanda had said the Nexus were doomed.
But then Captain Rodriguez burst in and debated about who he should kill. Fabian stood up. He was very drunk so he swayed and didn't speak properly, but he told Rodriguez not to kill Matt, because the Old Ones would be here soon and their lord Chaos would kill Matt anyway. So, Fabian refused to move for Rodriguez but the police chief finally had enough and shot Fabian in the chest.
Before Fabian died, he told them that there was no chance of stopping the satellite - the base wasn't in the house; it was out in the desert.