The Secret Fury, in many ways a run-of-the-mill romantic suspense drama (directed by Mel Ferrer) boasts top-notch principals in Colbert and Ryan; it stays puzzling if not quite gripping until towards the end, when implausibility conquers suspension of disbelief -- as so often it does in this genre. But for some viewers the film's highlight will be the portrayal of blowsy Leah by Vivian Vance -- the immortal Ethel Mertz on "I Love Lucy." Oddly, Vance had very few film roles; her true home was Broadway, where (among other gigs) she understudied for Ethel Merman. Here she contributes a winning turn as a chambermaid suborned to play a minor part in a nefarious scheme; watch her half-heartedly trying to wave away the smoke when she's puffing a furtive cigarette in the hotel's linen-storage room -- a transgression for which she ultimately pays the supreme penalty.