Bad Ass(2012)

They messed with the wrong senior citizen.

Decorated Vietnam hero, Frank Vega returns home only to get shunned by society leaving him without a job or his high school sweetheart. It's not until forty years later when an incident on a commuter bus makes him a local hero where he's suddenly celebrated once again. But his good fortune suddenly turns for the worse when his best friend is murdered and the police aren't doing anything about it.