Watch VoirFilms. Narcotics investigator Herbert Strähl is engaging in a fierce and seemingly hopeless battle against the drug scene on Langstrasse in Zurich. Carol is a wild young drug addict. Strähl's problems really begin when he falls in love with her. In his attempt to get Carol out of her disastrous environment, he increasingly finds himself in danger of falling into a vortex of dependence and violence.