Charles Bronson starts to break out of spaghetti westerns and good character roles and becomes a leading man around the time The Valachi Papers came out. It was a big milestone in his career, playing the most famous gangster stoolie of all.
It's not quite true that all Valachi's testimony managed to do was get a lot of high television ratings for some re-election hungry Senators. Not that they didn't get it and didn't appreciate the side benefits of those famous televised hearings, but eventually what came out of the Valachi hearings was the RICO law which has in fact put quite a dent into organized crime.
The Valachi Papers has Charles Bronson telling FBI man Gerald S. O'Loughlin about his life and times in organized crime with La Cosa Nostra from the days of the Marranzano-Masseria wars until the present which would have been 1962. He doesn't really tell anything new to them, basically he confirms what had been gangster legend about the circumstances of many a demise. But with some hard documentation now, new laws are created to meet the problem.
Bronson does his best with Valachi, but the story has him pretty one dimensional. It's far from The Godfather where you really get inside the characters of the fictional Corleone family. Bronson sure has no conscience about what he did and I'm sure the real Valachi didn't either. In fact the only reason he turns informer is that Vito Genovese already mistakenly has him down as one.
Fans of the gangster genre and Charles Bronson should give this one a look. Others should see The Godfather all three parts.