Act Your Age (1939)

Edgar becomes convinced that employees his age have no chance for promotion as the trend is to advance younger people. Unknown to him, he is about to be promoted to upper management because his boss thinks he is the only employee mature enough to handle to position. But the boss hires Edgar's replacement before he informs Edgar of his promotion, and Edgar, in a desperate attempt to save his job, begins to act younger both in manner and dress. This leads to his boss thinking that Edgar isn't mature enough for the job, and he hires Edgar's sixty-three-year-old retired and free-loading father-in-law (Billy Franey) for the position.