Story
First Squad (Japanese: ファーストスクワッド Fāsuto sukuwaddo, Russian: Пе́рвый отря́д, Perviy otryad) is a joint animation project of Japan's Studio 4°C and Russian authors with Molot Entertainment.
Plot:
Set during the opening days of World War II on the Eastern Front (autumn and winter of 1941/1942). Its main cast are a group of Soviet teenagers with extraordinary abilities; the teenagers have been drafted to form a special unit to fight the invading German army. They are opposed by a Schutzstaffel (SS) officer who is attempting to raise from the dead a supernatural army of crusaders from the 12th-century Order of the Sacred Cross (i.e. the Teutonic Knights) and enlist them in the Nazi cause. Most of the teenage crew die, except for the protagonist Nadia. She is taken to a secret Soviet lab that studies supernatural phenomena, especially contacts with the dead. Nadia's task is to dive into the world of the dead for reconnaissance. There, in the Gloomy Valley, she meets her dead friends and tries to persuade them to continue fighting.

[taken from Wikipedia]