Just as the GPS guides motorists along their travels, so does a DPS guide two people on a first date, by discretely alerting them to when they’ve gone too far or not far enough.
Tom, Dick and Harriet
Harriet is in love with Tom and Dick, and she wants a baby. She knows conception will make one man a father and the other an angry former lover. So, she devises an ingenious plan to get a baby without losing a lover.