Full Metal Panic: The Second Raid
Full Metal Panic: The Second Raid takes place about two months after the events occurred in the Tuatha de Danaan at the end of the original series. Mithril becomes aware of a secret organization that has technology able to counter the ECS (Electronic Cloaking System) mode.
This organization, known as Amalgam, also has "Black Technology", obtained from "Whispered" like Kaname Chidori, and like the other intelligency agencies, they intend to obtain more. However, when Sousuke's mission to protect Chidori is terminated by Mithril, all seems to be in place for Amalgam's plans.