It was also widely considered to be a dud, another misstep in a career filled with them, but over the years it has gained in stature. This despite the worse-than-horrible miscasting of Charlton Heston as a Mexican(!) detective in a border town. Supposedly the studio forced Heston on Welles and basically said, "deal with it". So he did.
The opening scene is famous for its opening take "long take" using a movable crane to follow a car from the time a bomb is placed in its trunk until after cruising through the streets of the border town, it crosses the US border and explodes. Reputedly Welles used up fully half of his filming budget on just this one shot:
That is, of all places, Venice California masquerading as the border town of Los Robles in this movie. Orson Welles is outstanding, even in the fake nose, as corrupt sheriff Hank Quinlan, and watch for some surprising minor-character near-cameos of Marlene Dietrich, Mercedes McCambridge and Dennis Weaver. If you watch that "long take" carefully, you'll also see an Alfred Hitchcock-like appearance of Welles himself crossing in front of the car as it is stopped at a light on the street.
In many ways it is Orson Welles' most personal film. He's played a lot characters who were destroyed by their own hubris (Charles Foster Kane, MacBeth, Othello, for example), and Hank Quinlan is no exception, but you can't help but see echoes of Welles and the studio system he fought for so many years in the machinations of Quinlan's desire to get the conviction, no matter what, thanks to that little "touch of evil" that everyone carries with them...
I can't praise this movie enough. I loved it so much that I even bought my own copy of the DVD, and I hardly ever do that. Highly recommended.