Professor Sing is a minor antagonist in Ark Angel.
Sing is employed by Nikolei Drevin and works with his rockets on Flamingo Bay, preparing them for launches and making sure everything is in order. After Drevin is killed on his island, Sing is forced to co-operate with the CIA as they try to stop Ark Angel crashing down on Washington. When Alex Rider is sent into space to neutralize the bomb onboard Drevin's rocket, Gabriel 7, the professor doesn't let anyone know that Kaspar has already gone up there to set it off. Alex manages to kill Kaspar inside Ark Angel and then tells the CIA that Sing double-crossed them, as he knew that Kaspar was there all along. Alex then returns home, and Sing is most likely arrested.