luce nelle tenebre (1941)

a mining engineer knows two sisters with a completely different character and personality: one is simple and reserved, the other is fatuous and vain, and it is this that the man undergoes the fascination to the point of asking her to be his wife. but the marriage must be postponed because the engineer must leave for turkestan to run a mine. during the absence he writes passionate love letters to the promised bride, but she escapes with an ancient suitor. in an accident in the mine, the man remains injured in the eyes; brought back home will be the sister of his girlfriend to look after him pretending the other thanks to a very similar voice. a surgical operation will restore the sight to the engineer who will thus be able to realize who really loves him and marry the right person.