Plot Hole?
SPOILERS BELOW
The entire plot between Jack Barlowe and the stewardess is built around them playing Ruth off as a distraught nut that commits suicide over an imaginary husband named John Bowman (aka Barlowe). Wouldn't Barlowe be exposed the moment he steps forward to claim Ruth's estate, as her supposedly imaginary husband John Bowman?
Was Barlowe working on behalf of the destitute Uncle Ed that Ruth mentions to the ship's doctor? Was it ever explained in the radio program from which it was adapted? Uncle Ed would seem to be the only person that could safely claim Ruth's estate, and then possibly pay off Barlowe and his girlfriend..
This would make for a good remake given the cruise ship foul play that seems to inhabit the news of late.