For the second time in the series, Cricket and Kim sing a duet of "The Hawaiian Wedding Song." (The first time was in the first season episode Then There Were Three (1960)).
Although not the season premiere, this episode finally added Grant Williams to the opening credits. Apparently not wishing to appear in swimming trunks, though, he is shown onshore, fully dressed, presumably waving to the others.
"Kapua" normally means "flower" or "child" in Hawaiian, but in this instance, it refers to a spirit that supposedly haunts Mama Mahina's island.