The official website for Saga of Tanya the Evil has now updated, and they revealed new details about the film. First up is the new teaser trailer they just started streaming:

The website also reveals the film’s story, which is an original one set in the aftermath of the TV anime’s events. With the Republic defeated, Tanya and her squad return home. However, as soon as they do, they receive word that the Russy Federation are the ones mobilising this time. But with their sights set on the Empire, the Russy Federation is also at war against an allied coalition led by the Allied Kingdom. The Empire tries to have an alliance against its former foe to combat the Russy Federation. However, Allied Kingdom ace, Mary Sioux still holds a grudge against Tanya for killing her father in the previous conflict.

The film will premiere in Japan on 8 February 2019. Aoi Yuuki will be returning as Tanya Degurechaff, while Saori Hayami is also returning as Visha. Aside from that, director Yutaka Uemura has confirmed he’s helming the anime once again over at Studio NuT.

Source: Saga of Tanya the Evil official website