When brash Texas border officer Mike Norton (Barry Pepper) wrongfully kills and buries the friend and ranch hand of Pete Perkins (Tommy Lee Jones), the latter is reminded of a promise he made to bury his friend, Melquiades Estrada (Julio Cesar Cedillo), in his Mexican home town. He kidnaps Norton and exhumes Estrada’s corpse, and the odd caravan sets out on horseback for Mexico. As Estrada’s body begins to rot, Norton begins to unravel, but Perkins remains determined to honor his vow.

Three different people in Mexico City are catapulted into dramatic and unforeseen circumstances in the wake of a terrible car crash: a young punk stumbles into the sinister underground world of dog fighting; an injured supermodel’s designer pooch disappears into the apartment’s floorboards; and an ex-radical turned hit man rescues a gunshot Rotweiler.