In New Orleans just before Hurricane Katrina hits, a pregnant woman gives birth prematurely. She dies and her baby is in critical condition. The baby has to be kept in a ventilator. When the hurricane strikes, all the power goes out and everyone in the hospital leaves. But the baby's father stays because the baby can't be moved so he has to take care of his baby by making sure the ventilator stays on. And because there's no power, the only power source is generator that he has to crank every few minutes. So he has to stay awake while waiting for someone to come for them.

Armando Alvarez (Will Ferrell) has lived and worked on his father's ranch in Mexico his entire life. As the ranch encounters financial difficulties, Armando's younger brother Raul (Diego Luna), shows up with his new fiancé, Sonia (Genesis Rodriguez). It seems that Raul's success as an international businessman means the ranch's troubles are over as he pledges to settle all debts his father has incurred. But when Armando falls for Sonia, and Raul's business dealings turn out to be less than legit, all hell breaks loose as they find themselves in a war with Mexico's most feared drug lord, the mighty Onza (Gael Garcia Bernal).