Insiders Project - Season 1 Episode 2 Underground tunnels of Arsenal factory

In this episode, the team sets on an expedition to Arsenal, which used to be a secret factory. Crawling inside narrow pipes, the shooting crew finds itself in the labyrinth of cellars connecting the whole factory underground. At the night the team gets out into the object's territory to walk through it all and see the power of Soviet industry - all the while avoiding military guard patrols.