The series follows Sousuke Sagara, a member of the covert anti-terrorist private military organization known as Mithril, who is tasked with protecting Kaname Chidori a hot-headed Japanese high school girl.
Voiced by: Yukana (Japanese); Hilary Haag (English) Teresa Testarossa (テレサ・テスタロッサ) is the captain of Mithril's submarine Tuatha de Danaan.
Voiced by: Shin'ichiro Miki (Japanese); Vic Mignogna (English) Sergent Kurz Weber (クルツ・ウェーバー, Kurutsu Uēbā) appears to be a typical ladies' man and often offers Sousuke advice about life and love.
Voiced by: Masahiko Tanaka (Japanese); Mike MacRae (English) Gauron (ガウルン, Gaurun) is Full Metal Panic's main antagonist, a twisted and violent mercenary deeply involved in the black market and global terrorism.
Despite possessing an extremely vile personality, his ruthless cunning and mastery of the Lambda Drive system make him a force to be reckoned with on the battlefield.
[3] Voiced by: Tomomichi Nishimura (Japanese); Andy McAvin, Mark Stoddard (Invisible Victory) (English) Richard Mardukas is an overly protective aide of Tessa, who insists on guarding her with his life.
Voiced by: Rikiya Koyama (Japanese); James Reed Faulkner (English) SRT team's current team leader, callsign Urzu-1, first appearance in the novel 'End of Day by Days' and the 2nd anime series Full Metal Panic: The Second Raid, replacing Captain Gail McAllen after his death near the end of the novel 'Rocking into The Blue' (and subsequently, the 1st anime series).
He also proved to be a capable leader when he made Sousuke understand why he lost and told him that it wasn't his skill as they were evenly matched in that aspect but rather his hatred for the Arbalest [7] and tells him that an Arm Slave is like a part of their own body.
He was also one of the few remaining survivors of the attack on Melida island, along with Melissa Mao, Kurz Weber, Richard Mardukas, Teletha Testarossa, and most of the crew of the Tuatha de Danaan at the end of the novel 'Continuing on My Own'.
Voiced by: Hozumi Gôda (Japanese); Jason Douglas (English) An American [10] MITHRIL officer in Intelligence with the rank of captain, he was supposedly responsible for communications maintenance in the Nanjing hostage rescue operation.
In return, Admiral Borda allowed a snatch operation to take place, which resulted in his capture and some strains in the relationship between the Tactical and Intelligence divisions.
[15] He's known to the Hong Kong public as a businessman with multiple businesses in operation, such as the Hunter Cleaning Company Ltd. that Gavin used when he provided Melissa's squad with Hunter Cleaning Company Ltd., Toyota Hiace vans and uniforms to infiltrate Hong Kong and Kowloon without being caught by the North and South Chinese army and police.
[16] He can be considered to be MITHRIL's humor character as Gates is to Amalgam's since he always smiles and rarely gets angry, except when he was instructed by General Amit to cease Intelligence operations in Hong Kong territory.
Voiced by: Kazuhiko Kishino (Japanese); Josh Grelle (English) The leader of Mithril's Operations department with the rank of admiral.
Borda is intended to be an homage to the late Admiral Jeremy Michael Boorda, the 25th Chief of Naval Operations of the US Navy.
Voiced by: Takayuki Sugo (Japanese); Matt Culpepper (English) The leader of Mithril's Intelligence department with the rank of general and of Israeli descent.
During the Second Raid series, he was the one who gave the order to MITHRIL officers to devise anti-infiltration countermeasures when he learned of Vincent Bruno's defection after the Nanking disaster.
[22] Voiced by: Daisuke Namikawa (Japanese); Blake Shepard (English) A child prodigy and Whispered like his younger twin sister, Teletha, he is known as "Mr. Silver" in the executive circle of the Amalgam organization.
[25] Voiced by: Miyuki Sawashiro (Japanese); Kira Vincent-Davis (English) A Chinese-born assassin, raised by Gauron alongside her twin sister Xia Yu Fan.
Later in Japan, she was killed by Leonard's man-size Arm Slave bodyguard named Alastor by strangling her to death, her corpse being used by Gates to mock Xia Yu Fan.
[28] Voiced by: Emi Shinohara (Japanese); Christine Auten (English) Another Chinese-born assassin was raised by Gauron and the "eldest" of the Xia siblings.
In the last episode, Yu Fan reveals that the Xia siblings were at odds with Amalgam, mostly for wiping out their town in China during the Second Chinese Civil War.
[28] Voiced by: Hōchū Ōtsuka (Japanese); John Swasey (English) An original character for the television animation 'Full Metal Panic!
Gates kills through a variety of methods including shooting an Amalgam commando in the head when he backtalked and crushing Xia Yu Fan's Shadow Arms Slave with extreme ferocity.
Despite such brutality, Gates showed his intelligence by being able to deduce accurately the tactics that MITHRIL's Special Response Team utilized in their intervention in the Balic civil war.
In the same scene where he finds out that the girls have escaped, it depicts him being interrupted in the process of masturbating over the image of kittens on his wide-screen TV.
On many occasions involving the school, Sousuke tends to treat Atsunobu just as he would a senior officer in the military, even to the point of calling him "Excellency" in the English dub.
Because women in the time of the Tokugawa shogunate were given names with two syllables only (usually adding the prefix "O-" to refer to someone of higher social standing and considered an honorific), Kaname prefers to address her as Oren-san.
All he wants out of life is to please who he thinks is his big sister, Seina, (since he killed his actual one) but she's been scarred and vowed revenge against society long ago.
Secondly, during the events of the novel, 'Dancing Very Merry Christmas', Sailor is a passenger aboard the Pacific Chrysalis when Amalgam activates Harris and a force of Alastors.