The leader of the Jönsson gang, Sickan, is institutionalized and creates a handbook on crime that catches the attention of his psychiatrist, Dr. M.A. Busé. Under pressure from the cunning banker Wall-Enberg, Busé and Sickan's accomplices Vanheden and Dynamite-Harry orchestrate a daring heist to steal the priceless Black Diamond of the Romanovs from the National Museum.
Jönssonligan & den svarta diamanten
A clever convict, locked away in a psychiatric hospital, orchestrates a scheme with a compromised doctor and trusted associates to carry out his illegal objectives.
