Some day Hollywood is going to stop kidding itself about the average American mentality. They claim that it's equal to that of an eight year-old child, but they keep putting out pictures that a four-year-old would have a hard time digesting. The double bill at Keith Memorial is a perfect case in point. It consists of "Son of Monte Cristo" and "Play Girl," two of the corniest pictures that have graced the screen since Victor Mature went native in "1,000,000 B.C." "Son of Monte Cristo" is an attempted imitation of the grand old Douglas Fairbanks self-admitted horse opera and right now Douglas is probably doing a couple of agile back flips in his grave. Everything about it is weakly done: the acting, the direction, the sets, and the plot. Even George Sanders, of whom much more should be expected, fails to rise to the occasion. He plays the part of a villainous usurper by the name of Gurko who is seeking the throne and the hand of Joan Bennett. Joan, however, knows better and with the help of the second of the Cristo line she foils him in every respect. This fellow Cristo (Louis Hayward) is less convincing in his portrayal of virility than is Alice Faye in the role of Virtue Rewarded. The one slightly redeeming feature of the picture is Gurko's right-hand man, a strange mixture of Akim Tamiroff and the master of Mike's Club. Though half the time it's hard to tell whether he's trying to look silly or insidious, he nevertheless stands out brightly against the rest of the cast merely by virtue of a perfectly unconscious imitation of Billy Minsky's one and only stinky Finkelman.