I saw this one back in 1981 and it's commercial title was "Diente por Diente" which means a teeth for a teeth. I remember I was quite impressed for the suspenseful quality of his flick. Years later, by the turn of the century, I made a list of several films I had seen in the past and that where in some way outstanding, and of course, "El Crack" was one of them... but it wasn't available anywhere (I was near at one place who had had it but the tape had gone into pieces). Again, many years later, -26 exactly since its original release- I finally find it, and start watching it with very different eyes: those that 26 years add to your life experience. At first, the first 1/2 hour, the film looks somewhat vulgar and filled with apparently unnecessary details of the main character, but then it starts to raise and raise (which is a unique quality of good films), with very good and unexpected twists. All in all, this is a very good movie and in case you have it at hand, don't miss it. I also found "El Crack 2", a kind of sequel made 2 years later, which I had never seen before. It's not so good as the first part, but it's good and worth watching also. I gave the first part an 8 and the sequel a 7.