A mysterious Major Gaspar commands the Chetniks in Belgrade. Prle, Tihi and Joca have to return to Belgrade posing as government officials. Unaware of their identity, the Germans, the Partisans and the Chetniks all hunt for them.
Downed American paratroopers must be saved from the German encirclement in a village near Belgrade so Mrki, Tihi and Prle hatch a plan. Krieger and Misic search Marija's building after a tip from Prle's old friend, Dragi Kenta.
Prle, Tihi and Mrki must capture and interrogate a secret police agent Dvokrilac to learn the location of the radio transmitter which the Germans plan to use to find their secret radio station.
Abwehr send Dr. Grothe to help Gestapo infiltrate the Partisan cell in Belgrade, so they use a double agent. Krieger is convinced Grothe is a traitor so he enlists Marija to help him prove it.
