George Vraca
— professor Dan Olteanu
Irina Răchițeanu
— Anca Olteanu, Dan's wife
Jules Cazaban
— colonel Jack Paleologu
Fory Etterle
— engineer Tasca
Ion Lucian
— Virgil Sachelarie, professor Olteanu's assistant
Grigore Vasiliu-Birlic
— Mișu
Mircea Constantinescu
— professor Cristea
Graziela Albini
Sanda Costiniu
Ion Henter
— foreign agent Spiridon Dumitrescu
