Parti ouvrier polonais
Mołojec was attached to the "Initiative Group" parachuted into Nazi-occupied Poland in December 1941, to establish the Polish Workers' Party (PPR). With Marceli Nowotko and Paweł Finder, he formed the leadership troika. He was in charge of the generally unsuccessful efforts to establish a military underground, the Gwardia Ludowa, and launch guerrilla warfare against the German occupation forces.