Diane Baker is back, no longer a mermaid but still alluring. Improbably, she's the daughter of widower Lon Chaney Jr., who is reminded of her vixenish mother. Diane shows some of the same traits, getting involved with Linc and then with a sailor played by Alex Vespi, (better known as Alex Cord- the first of three appearances this season). To quote James Rosin in his book on the series, "in the same manner as in which he sails from port to port, she drifts from man to man. Marie realizes she must find herself." Somehow that involves going on the road like- or with- Tod and Linc. But she's persuaded to stay home to care for her crippled father and try to find herself there.
To be honest, I really didn't get it. She needed to anchor herself and I didn't see why leaving home would give her that anchor. Also, the tepid love triangle in this story didn't suggest that she was all that promiscuous, although maybe they had to just imply it in those days. And Diane Baker, as lovely as she is, isn't really the vixen type.