Crew leader Horst (Willi Thomczyk), with his two underlings Kalle (Ralf Richter) and Kummel (Hilmi Sözer), is ordered by their boss, Werner Wiesenkamp (Dietmar Baer), to work with the young architect Philipp (Thorwarth). Horst takes this personally, especially when the architect starts hitting on Horst's daughter Astrid (Alexandra Maria Lara). Playing a number of humbling pranks on Philipp whilst on the scene of their newest work site, the builders discover an unexpected complication: an undetonated bomb from World War II lying where the foundation of the building is to be laid.