Successful plays aren't often transformed into successful motion pictures without a somewhat drastic application of the "movie technique." An exception was "Night Must Fall," which three or four years ago was lifted almost bodily from the stage to the screen, and was equally effective in its new medium. Following closely in this tradition is "Ladies in Retirement," last year's number one Broadway mystery drama, and one of this season's first-rate cinema thrillers.

Without the aid of weird musical effects and somber, "arty" camera angles, "Ladies in Retirement" packs as much terror and suspense as a dozen of Hollywood's more pretentious spinetinglers. There are a couple of shots of mist-covered marshes to lend atmosphere at the beginning, and the musical background does furnish a few minor chords at the right moments; otherwise the story moves along--with its train of sinister over-tones--of its own weight. The effect lies in the story itself, and in some excellent direction, not in the well-aimed camera that has made so many films seem far better than they are.

Ida Lupino, proving again that she ranks among the screen's top-flight actresses, gives a restrained and intelligent performance as the murderess who kills her benefactress in order to provide a home for her two helpless sisters. Louis Hayward is excellent as her conniving nephew. And each of the supporting roles is masterfully handled, with an attention to detail that fills every scene with an unmatched intensity and impact.

"International Squadron," the second feature on the bill, has some scenes from "Blitzkrieg im Westen," a few airplane action shots of its own, and a pointless love story. The result is a spotty rehash of "A Yank in the R.A.F.," better in some of its air-raid sequences but an inferior job in general. Right now, those bombs don't look fictitious enough.