When country music singers Wilder & Grace, a side act stuck on a bare-bones tour with a has-been southern rock band, stop at a lonely Arizona diner at two in the morning and find an abandoned backpack full of banded $100 bills, Grace impulsively grabs it. Money like that could make their dreams come true. Instead, it's the beginning of their worst nightmare, setting off a desperate pursuit across the West with nowhere to hide.

What Grace couldn't know was the wayward backpack was first stolen by cartel boss Luis Reynaldo's mistress, joining forces with his favorite assassin. They seize an opportunity to get away from their homicidal overlord after a drug deal in Oklahoma City goes disastrously wrong. Once Luis discovers Angel and Chang are not among the casualties, he obsessively sets out to exact his revenge. Both couples on the run find they must do whatever it takes to escape their old lives and create the futures they crave, but the risk and the bloody toll become increasingly higher.