In the new movie The Juddge, when the title character– Judge Joseph Palmer (Robert Duvall)– talks about the attorney he needs to defend him in an upcoming murder trial, he notes that someone decent would serve him well. He adds, “By decent I mean honest”– two adjectives that could easily describe his own character.

He’s served his nation and his hometown for 42 years as a criminal judge and has been an honest, decent man throughout those years in court. He’s done his civic duty of protecting the innocent and punishing the criminals and believes that he deserves some respect from both the community and his own children.

When his wife dies as the story begins, Joseph’s wayward son Hank Palmer (Robert Downey Jr.)— now a high-profile attorney— returns to town to mourn his mother. He doesn’t show his father much respect. Hank is efficient both in the law and in relationships. He dives into both relationships and cases, does what he wants and then leaves as soon as it’s convenient for him. He plans to do the same thing at his mother’s funeral— rushing into town, saying his goodbyes and then leaving before the dawn breaks on a new day. Hank’s plan is jilted when his father is accused of murdering a criminal who once stood in his courtroom.

Hank is forced to dig deeper and expect more from himself, something he’s never been good at.

The Judge provides a perfect opportunity for two actors— one still in his prime and the other a walking, talking, living legend— to show off their dramatic skills and to create complex and flawed characters. Downey Jr. may be the bigger star now but it’s Duvall whose vulnerabilities show through his every moment onscreen. Joseph, like his son, is a stubborn man but needs physical care for his ailing body. One second the judge may be in charge of a packed courtroom but moments later, he may be incapable of managing his own faculties.

It’s to his credit that Duvall is able to show off the duality of this character so magnificently.

Vincent D’Onofrio and Jeremy Strong appear as Hank’s two more responsible siblings Glen and Dale. Glen has stayed in town with his parents while Dale is mentally handicapped and has always relied on his parents. But the show here belongs to Downey Jr. and Duvall and Vera Farmiga, who plays the lovely bartender whose relationship with Hank is brought into focus when he’s back in town.

Despite its title though, The Judge doesn’t spend the majority of its running time in a courtroom. Instead screenwriters Nick Schenk and Bill Dubuque rely on the familial relationships to keep this story going. If the characters aren’t written well, the verdict (is the judge guilty of murder?) wouldn’t matter. Here, the characters are written so well that the verdict matters a great deal.

While The Judge hits its mark during the many scenes that Duvall and Downey Jr. share, it falters in its depiction of some of its less important relationships. Downey Jr.’s marriage is surprisingly underplayed here— in fact the argument he has with his wife feels completely out-of-place. Additionally, Hank’s relationship with a young bartender named Carla (Leighton Meester) is both unnecessary and distracting from the larger story being told here.

This is a movie about a father and a prodigal son and when it so often arrives in those moments, the verdict is clear: this movie is a winner.