The Veil (1958)

A captain returns from a sea voyage to a wife he does not love. He saves her life after she is bitten by a snake. He almost immediately regrets having done so, as he learns that a woman who is smitten with him has been recently widowed and has inherited a large sum of money. He plots his wife's murder, but will he succeed in his plans even if he is successful in ridding himself of his cumbersome wife?