A symbolic depiction of hell on Earth, set in the last days of the Warsaw uprising in 1944. Lieutenant Zadra is commanding a company of 43 men in a desperate battle amidst the ruins. Facing German offense and cut off from their comrades, Zadra is commanded to retreat his men through the sewer system ('kanal'). Zadra and his men are reluctant to do so, as it would indicate that they have lost the battle, but decide to obey the orders. However, as the men (and women) retreat, it becomes clear that their desperate attempt to flee from the hell of battle will result only in more death and suffering...