We previously reported that Retsu Tateo and Shoji Gatoh’s Full Metal Panic series would be receiving a fourth television anime as of this fall; however, at this year’s Anime Expo, it was announced that the fourth season would be delayed until Spring of 2018. The full title of the new season will be Full Metal Panic: Invisible Victory.
FUNimation did show off a promotional video at Anime Expo in which the villain Kurama and Amalgam soldier Lee Fowler will debut in the anime. Both characters are from the light novel series. New mecha and character designs were shown as well, including Mao who was promoted to lieutenant. XEBEC is still on board as the studio that will be producing the anime.
MyAnimeList.net describes the story of Full Metal Panic! as follows:
A sergeant by the name of Sousuke Sagara is assigned an important task. That of guarding high school girl Chidori Kaname. Sousuke is a military genius, gaining high rank at an early age, but because of his strange upbringing, he lacks social skill. Now, he finds himself as a fish out of water as he attempts to protect a girl from an evil organization and turn in his school work on time.