The Bank Dick (1940) -720p, for better quality see comment below- W.C. Fields, Una Merkel, Dick Purcell

Egbert Sousé Fields) becomes an unexpected hero when a bank robber falls over a bench he's occupying. Now considered brave, Egbert is given a job as a bank guard. Soon, he is approached by charlatan J. Frothingham Waterbury (Russell Hicks) about buying shares in a mining company. Egbert persuades teller Og Oggilby (Grady Sutton) to lend him bank money, to be returned when the scheme pays off. Unfortunately, bank inspector Snoopington (Franklin Pangborn) then makes a surprise appearance.