On the Red Front () is a 1920 Soviet silent war drama film directed by Lev Kuleshov.
During the Russian Civil War, the commander of a Red Army unit entrusts a courier with a secret report to deliver to headquarters. Along the way, a Polish spy ambushes the courier, steals the confidential document, and attempts to escape.
Undeterred, the Red Army soldier pursues the spy, with the help of a passing vehicle that allows him to catch up to a train where the spy has taken refuge. The two engage in a dramatic fight atop the roof of a railway carriage. After a fierce struggle, the Red Army courier defeats his opponent and successfully delivers the critical dispatch to headquarters.