Grandpa Earl, it's Grandma Mary

Earl Stone, a man in his eighties, is broke, alone, and facing foreclosure of his business when he is offered a job that simply requires him to drive. Easy enough, but, unbeknownst to Earl, he's just signed on as a drug courier for a Mexican cartel. He does so well that his cargo increases exponentially, and Earl hit the radar of hard-charging DEA agent Colin Bates.