That's too bad, because Gringo has a lot going for it, including
some occasionally sharp dialogue (by either Matthew Stone or Anthony Tambakis, who contributed to the bonebreaking and tearjerking Joel Edgerton / Tom Hardy MMA drama Warrior) and a quartet of funny performances from players not primarily known for bringing the yuks: L'il Edgerton, Charlize Theron in full femme fatale mode and beardy heavy Sharlto Copley.
Julian Mitchell's script tends to drag its feet, if not cut short a lot of expository depth, but it keeps consistent on razor -
sharp dialogue,
occasionally broken up by witty humor that puts a bit of kick in the slower spots, about as much as highlights in Brian Gilbert's direction which break up slow spells and sentimentality with occasions of color and effective thoughtfulness.