Finnish songwriter and artist Juice Leskinen has depicted this phenomenon chillingly in his song Osapäivänatsi (Part-Time Nazi), where a father takes off his uniform and jackboots after a hard working day, kisses his wife and plays with his children. He demonstrates how this kind of villains usually are the most dangerous as they are fully able to compartmentalize their ethics and their actions in two neat separate boxes.
"Just a Job to Do" by Genesis.
The music video for "Genghis Khan" features Miike Snow as one of these. The unnamed mastermind postpones killing a dapper spy with a laser beam because at precisely 5 o'clock, the lights go low and it's time for him to go home to his perfectly normal wife and kids.