Detective Virgil Tibbs as played by Sidney Poitier

At a time when race relations and tensions were running high, civil rights had got going in America.  'They call me Mister Tibbs!' shouts the first black policeman in mainstream cinema. Audacious and humble, this African-American from the North refused to be intimidated by the Mississippi racism that enveloped the South at that time. 
Best Bit: When he slaps the white plantation owner. Take that prejudice! ” 

Mr Tibbs represents the changing point in attitudes towards African Americans in America. 

Johnny Boy played by Robert De Niro

The entrance scene captures the heart of the movie 'Mean Streets' and at the movie's centrepiece, Johnny Boy, played by Robert De Niro, appears with a blond and brunette on each shoulder. Rolling Stones' 'Jumpin Jack Flash' plays out, capturing the volatile and unpredictable nature of the character. Not only is he a comic relief to a film which plays around the darkness of the Italian Mafia in Philadelphia, but he is also the linking and separating device between 'Charlie' played by Harvey Keital and his cousin Teresa. He is self-destructive but also destructive of others around him and this reaches a climax at the end of the film.