Fliegende Ratten (2006)

Chris, a petty thief, plans an armed robbery doomed to failure. His girlfriend Elena tries everything to keep him from ruining both their lives. As the hot August Sunday passes, Chris gets drunker and drunker. The newly aquired gun in his pocket gives him a feeling of power as he drifts through the neighborhood park looking for trouble. Elena sees the tragedy unfold, but seems unable to get through to him.

Unfortunately the movie Fliegende Ratten is not yet available on HBO Max.