Dwaj panowie 'N'
From The Internet Movie Plane Database
English title: Two Gentlemen 'N'
Joanna Jedryka (Elzbieta Brylska)
Janusz Bylczynski (Engineer Henryk Nowak)
Stanislaw Mikulski (Sgt. Jan Dziewanowicz)
Waclaw Kowalskir (Tradesman Henryk Nowak)
Bohdan Ejmont (Maj. Olecki)
Boleslaw Plotnicki (Kazimierz Dziewanowicz)
Kazmierz Dziewanowicz's hobby is very strange. He collects people who were born on 29th February. One day he sees that in his collection there are two men with the same name, the same birth place, the same date of birth and the same parents. In the middle of the night somebody kills him. The Intelligence Agency begin an investigation.
Registration SP-LSA, serial no. 2403.