Vodovod ("The Waterworks" in English) is the tenth episode of the drama television series Povratak otpisanih, originally aired on Yugoslav Radiotelevision network (JRT) on March 5th 1978. The plot deals with Belgrade resistance trying to prevent retreating German troops from blowing up city's water supply.

Prle is met by his old gymnasium friend Lale "Pufna" who tells him that he noticed that a SS woman in neighbourhood collects water into bottles for last three days. Lale concluded that the Germans plan to destroy Belgrade's water supply and that the woman received advance notice. He tells Prle that he knows that he is within resistance and offer to join. Prle is skeptical at first and worried that an old friend might be enemy agent.

Marija is still seemingly enjoying company of Gestapo Major Krieger who brings her to a ball. He is suddenly called and must leave the party, but arranges Marija to be brought home by his driver, causing jealosuy among two women who had less success in wooing affection of German officials and who now almost openly contemplate possible haircuts and other punishments from Communists when they take over the city.

When Marija returns home she tells Tihi, Mrki, Prle and Joca that Krüger has been called over something related to city's water processing plant.

This is enough for Tihi to bring Prle and Mrki to talk to Uncle Marko, one of water processing plant workers.

When they leave apartment, they are greeted by Lale who apparently had Prle followed.

Prle tells him that they will discuss matters at Lale's home and later tells Marija and Joca to prepare to impromptu evacuation in case Lale is an agent and their location is known to the enemy.

When Prle visits Lale's apartment, he can't fail to notice that it is luxurious.

Lale explains that his parents, rich merchants, have fled the city and left him alone.

Lale offers his old friend with Grand Marnier and Courvoisier cognac - liquors that are unimaginable luxury for citizens of occupied Belgrade. Lale asks Prle to help him join the resistance, even if such resistance is Communist. Prle responds that he is actually a double agent who works for both sides and occassionally gives up his Communist contacts; he tells Lale that he is doing him a favour by refusing to bring him along. Lale reacts by physically attacking Prle calling him traitor. Prle wins the brief but fierce fight and tells Lale that his story was a test he ultimately passed and that he can join the resistance.

Cane Kurbla drives his truck towards water processing plant and from it Prle, Mrki and Uncle Marko observe it.

Uncle Marko tells about number and position of German soldiers - Waffen-SS and combat engineers. Most of the guards retire after 21:00 when the fence is powered. Tihi decides that it is the best time to strike.

On the night when Tihi's group is about to attack the plant, German commander gathers Uncle Marko and his workers and has all of them locked in one room.

Uncle Marko knows that Germans are planning to blow up the plant very soon and desperately tries to dig through the walls.

They only succeed in making little hole in the wall which would allow them to observe Germans in main engine room.

Tihi, Prle, Mrki and few other resistance activists, including freshly recruited Lale, were waiting for Uncle Marko to switch power off and allow them to penetrate facility through fence.

Since he didn't give signal, they know something was wrong and change plans on the fly.

Guard outside is quietly taken out.

One of German officers is captured and the workers in the room are liberated and given weapons.

When the firefight starts, Uncle Marko proves useful by shooting Germans in the back from the hole in the wall.

Resistance overwhems the Germans who are killed or taken prisoners, except one who managed to hide.

While Uncle Marko and his workers start to remove explosives, Tihi decides to celebrate and sends Lale outside to bring food from the truck.

When Lale returns, he stumbles on German officer who shoots him.

The officer is shot immediately afterwards, but it is too late for Lale.

Prle is devastated with the death of an old friend.