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Sickan, Vanheden and Rocky try to rob the Berns nightclub one night, but Vanheden has made the mistake to invite his constantly drunk cousin, the old dynamiter Dynamite-Harry and he ruins the plan. Sickan is arrested, and has to spend 10 months in a small, locked room. When he is released, he has a new plan, but Rocky and Vanheden have decided to go straight. Together with Dynamite-Harry, Sickan plans to rob a cold store, managed by their arch-enemy, Wall-Enberg.