The Mating Game (1959)

Uptight IRS man Lorenzo Charlton (Tony Randall) is ordered to investigate rural rancher Pop Larkin (Paul Douglas), who is significantly in debt to the government. Lorenzo arrives in the country and is shocked to discover that Pop and his family are so oblivious to financial concerns they haven't ever bothered to do their taxes. Some moonshine, however, and Pop's lovely daughter, Mariette (Debbie Reynolds), help Lorenzo learn to relax, and he decides to help the Larkins' find a legal loophole.