This film is another one that highlights the racism that was still present in the south, even after the Civil Rights Act, but isn't as overt as Mississippi Burning. Sidney Poitier plays a police officer from Philadelphia, who is first accused of a murder and is then commissioned to help solve it. This film is also set in Mississippi, and the sheriff in the town is prejudiced against him, but needs his help.
This film was released in 1967, during a time when racism and bigotry were still commonplace (I know racism still exists, I'm not ignorant of that, but I think that those who lived during the 60's experienced overtly racist comments and interactions more often). It's another film that can make you mad, but it's good to see. I don't want to watch these movies all the time, but I like films that make you stop and think.
And I'm not the only one who likes this film, it won five Oscars including best adapted screenplay, best actor and best picture. So you don't have to just take my word for it.