Film buffs, what is the French Connection about, and what is the over arching message of the movie?

It's loosely based on a real story of cops investigating drug smugglers in the late 60s. Gene Hackman and Roy Scheider play Popeye Doyle and "Cloudy" Russo, a pair of NYPD detectives who stumble on a major heroin smuggling operation. It's inspired by a real life smuggling operation based out of France and run by French and Corsican gangsters. They smuggled heroin from Turkey, through France, and then to the US, hence the name.

I don't know that the film had strong themes. It's really a crime drama. What made it stand out was the aesthetic. It was shot in a much more gritty style than crime dramas at the time, depicting a very dirty and decaying New York City. The cops trying to hold it together were also darker than most of the cinematic cops of the time. They rough up suspects and don't espouse much of a moral code. There's also a theme of bureaucracy as Popeye and Cloudy try to, initially, push their case uphill against the skepticism of the police brass. It hits a lot of thematic elements that the Wire would also play with thirty years later

I didn't care for it, I thought Hackman miscast. Someone a lot better looking, and younger, like McQueen. McQueen Can Drive, too. He looks better in bed with a girl. Hackman looked like her Grandpa. Too Old.

Towards the end of his Bond movies, Roger Moore started looking too old, too.

A NYC detective and his partner who are assigned to the drug department accidentally come across an international drug smuggling operation. The detective never gives up in his pursuit of the ring leader.

That's all I can say without spoiling a fine action movie which won best picture at the Oscars.