While walking along the beach on his last evening in Honolulu on a week long trip, Stuart comes to the rescue of a woman being attacked. While he is able to subdue and apprehend the attacker for the local police to take into custody, Stuart discovers the next day that he actually interrupted an undercover federal operation in progress. A couple of counterfeit bills have surfaced on the island, they believing that they were circulated by mistake within a larger scheme to flood the island, but knowing the counterfeiter is Daniel Grayson, with the issue being that he is currently incarcerated in a federal prison on the mainland. The feds have to figure out how he is getting the counterfeits to the island and who his distributor is/will be. His only known connection to the island is nightclub singer Faye North. The attacked woman is Faye's friend, Martha Swain. The attack was a means for who they had as their "knight in shining armor" come to rescue Martha befriend her and in turn befriend Faye. As they cannot stage another attack and rescue, they instead ask Stuart to continue with the operation in place of their "knight", to which he agrees much to Jeff's chagrin in having to carry an extra load on a case back home. While Stuart is able to befriend Martha and eventually Faye in the process, he will find that they are like night and day: Faye is beautiful and confident, while Plain Jane Martha lacks any sense of confidence, especially when it comes to men. A problem ends up being Martha developing feelings for Stuart, who in his undercover role has to woo Faye instead, he, as a gentleman, not wanting to hurt Martha solely as collateral damage of the case. This problem ends up having a consequence to the case as it relates to one important issue that is not quite what it appears on the surface.
—Huggo