"Every Saturday Night" and "The Preview Murder Mystery," contrary to the conventional double-feature bill that relies on one first-class picture to draw the public and lets the other pass as a sop to time, are both highly amusing. The two movies at the Paramount and Fenway, though not exceptional, have no periods of "let-down" and are consistently entertaining.

In "Every Saturday Night" we are taken into the family-problems of a father with five typical children, ranging in years from 6 to 18. Pa Jones insists on running his elder son and daughter according to the rules of his youthful days. There is the pleading for the use of the family car, the warning to come home before twelve, and the troubles of a son's meager allowance that hearken back to days not far remote for many of us now. After continued rebukes for his nagging by his own old mother, and his 17-year-old son's timely first-aid treatment of a little brother, Pa Jones finally softens up, rewarding the boy with a secondhand car and an ample allowance. The cast, aside from June Lang and Thomas Beck, is not well known.

Reginald Denny, with his nicely twisted gentleman's moustache is the man who somewhat naively solves "The Preview Murder Mystery." The plot hinges upon a cinema director's suspicion that his actress-wife, Gail Patrick, is in love with the hero of a film which he has just finished. Threatening notes warn the actor that he will never live through the preview, and true to form, he doesn't. Two more murders are committed before Denny, a movie publicity man, discovers the criminal. We warn you not to be too gullible in accepting obvious clues, because Paramount, Inc., is bent on deceiving you.