Serge Merlin as Jakub Gold

Alina Janowska as Lucyna

Elżbieta Kępińska as Kazia, Malina's Niece

Jan Ciecierski as Józef Malina

Tadeusz Bartosik as "Professor" Pankrat

Władysław Kowalski as Fiałka / Jakub Gold (voice)

Irena Netto as Jakub's Mother

Beata Tyszkiewicz as Stasia

Jan Ibel as Genio

Bogumił Antczak as Prisoner (uncredited)

Wiesława Chojkowska as Wiśka (uncredited)

Edmund Fetting as Zygmunt, Guest at Lucyna's Party (uncredited)

Roland Głowacki as Guest at Lucyna's Party (uncredited)

Andrzej Herder as Gestapo Officer (uncredited)

Zygmunt Hübner as Gestapo Officer (uncredited)

Zofia Jamry as Woman Blackmailing Malina (uncredited)

Stanisław Jaśkiewicz as Professor at a Lecture (uncredited)

Zbigniew Józefowicz as Guest at Lucyna's Party (uncredited)

Edward Kowalczyk as Policeman (uncredited)

Zygmunt Listkiewicz as (uncredited)

Jerzy Łapiński as Caroller (uncredited)

Zdzisław Maklakiewicz as ONR Member (uncredited)

Zygmunt Malawski as Printer (uncredited)

Roman Polanski as Partner of Malina's Blackmailer (uncredited)

Ryszard Pracz as (uncredited)

Ryszard Ronczewski as Prison Guard (uncredited)

Magda Teresa Wójcik as Woman at Lucyna's Party (uncredited)

Tomasz Zaliwski as Prisoner (uncredited)

Andrzej Żuławski as Killed Student (uncredited)