In extreme emergency, Bernd Roland and Toni Burian have to leave the moving train on the free route. Bernd Roland is injured when jumping. But he manages to stop a hospital car and give the order to take him and Burian to Berlin. Having arrived in the capital, Roland, Burian and the Soviet scout Boris (Gunter Schoß) do everything in their power to successfully complete their instructions. In concrete terms, this means finding out what plans the SS has for the last battles for Berlin.

Secret operations unit "Spree" was the sequel to the scout films “Secret operations unit Boomerang” (1966) and “Secret operations unit Ciupaga” (1967). In the spring of 1945 it was definitive: the final defeat of fascist Germany was inevitable, only a few weeks left, then the Hitler regime would be history.