The leftist forces are retreating north as Franco’s army advances with the help of German and Italian aviation. Max Friedman approaches the front, posing as a photographer in a small group of foreign journalists. He flashes back to battles fought with his old comrade Guido Treves, who has gone missing and is the object of his mission. Amidst the ruin of war, Claire, the pretty Belgian reporter who got Max his press credentials, is developing a strong attraction to him, arousing the jealousy of her fellow reporter and would-be-boyfriend, Phil Lester. Caught in the middle of a retreat, Max and Claire get separated from the rest of their group. They have to cross a mountain pass and take shelter in a hut — the romantic tension builds, but gets snuffed by the urgent need to press onward.