Assassin-for-hire Alex Lewis (Liam Neeson) has Alzheimer's disease and is slowly losing his memory. Although he wants to quit the business and retire to live the rest of his years in peace, his Mexico City contact refuses to hear it. He gives Lewis a huge amount of cash to kill two people in El Paso, where the hitman was raised.
Lewis kills the first one, an adult businessman, but discovers his second target is an orphaned 13-year-old girl (Mia Sanchez), who's an undocumented immigrant. When he refuses to kill the girl, Lewis becomes a target himself.
A remake of the 2003 Belgian film The Memory of a Killer.