Like the real-life Sharpe, Eastwood's character, Earl Stone, is first shown as a gregarious and successful horticulturalist and celebrity breeder of custom day lilies who is admired and honored. However, beneath that we also see that he is a consummate workaholic who is so enthralled with the fame, adulation, and wealth his success has brought him, that he completely neglects his family and caused the breakup of his marriage. We see how he missed the day of his own daughter's wedding so that he could attend a horticultural convention to receive a prestigious award.
The movie then shifts to a few years later as his business and home are about to be foreclosed on. He pays his workers their last paycheck before heading off to his granddaughter's wedding engagement party, who is the only member of his family he has any relationship with. There, after arguing with his ex-wife and the daughter whose wedding he missed, Stone meets a young man who gives him a card which connects him to drug runners who eventually offer him a job delivering drugs because of his spotless driving record.
From there the movie shows Stone making a total of eight runs, all the while DEA agent Colin Bates (wonderfully played by Bradley Cooper) and his partner Trevin (Michael Peña) are trying to find him based only on the description of his truck and his nickname, "El Tata" (the grandfather).
In between runs, he spends money on his friends and especially his granddaughter to put her through school, all the while trying to reconcile with his family. As he becomes increasingly successful at his work, he is given a handler who watches his every move and is even brought to Mexico to meet the cartel boss El Laton (played by Andy Garcia).