Bad Ass (2012)

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 40 years later when an incident on a commuter bus where he protects an elderly Black man from a pair of skinheads makes him a local hero and he's suddenly celebrated once again. But his good fortune suddenly turns for the worse when his best friend Klondike is murdered and the police aren't doing anything about it.