A gang of robbers takes possession of a load of diamonds.. Only one of them, Mark Lemmon, is arrested and sentenced to life imprisonment. But before being captured, the gangster had managed to hide the loot in a sewer. Five years later, Mackenzie, an insurer, pretending to be a mafia boss, assigns three petty criminals to arrange his escape. Once free, Lemmon finds the booty but now he has to deal with his new 'partners'.

Hamburg business man Otto Westermann is also the boss of organized crime in the city. His reign as godfather is in danger, though, as an ambitious Sicilian mafioso enters the fray. His goal is clear and simple: he wants to take over Hamburg. But Westermann isn't as easy to defeat as the Sicilian expects. And soon Hamburg is on the verge of a bloody mob war.