Detective Robert Whitmore (Stephen Hardy) is in for a surprise when he is assigned a new partner — his grandfather (Garry Nation) whom he blames for the loss of his father as a boy. Due to a clerical error, Grandpa, a retired detective, has been forced out of retirement after twenty years.

As the two generations try to solve an increasingly difficult case of the biggest, baddest, most brazen thief the department has ever seen, Whitmore is forced to deal not only with Grandpa, but with his feelings of bitterness and his own standing before God. My Grandpa Detective is a humorous story with a serious message of family and forgiveness.