Anne Francis plays the femme fatale in this film noir-structured episode, with plenty of evocative Stirling Silliphant dialogue to captivate the viewer. It was directed by veteran Lewis Allen, whose many successful movies include classics like "The Uninvited" and the Sinatra-starring noir "Suddenly".
Told in flashback form (from Maharis' point-of-view) it varies from the series' usual format in that it's set in Malibu, California where M & M have a brief vacation by the ocean, with the atmosphere of West Coast jazz, rather than interacting with a local community.
Francis attaches herself to the boys after a near-accident of her bad-brakes station wagon almost hitting the Corvette. Her domestic problems with top jazz trumpeter husband Jack Lord enmeshes M & M, and the marital conflict takes center stage as Anne feels trapped by not Lord's fame but his possessiveness, though at first we're led to believe that everything is the neurotic wife's fault.
Maharis finds a kindred spirit in a jazz singer "Kitty Parker" (of course a reference to Charlie Parker's wife Chan Parker, whose daughter Kim Parker became a jazz vocalist), beautifully played by Barbara Bostock (whose acting career never really took off). But it is the clash between an otherworldly Lord, constantly trying to be transported to another sphere of reality through his playing, and the trapped wife who cannot fully accompany him or escape his clutches. Milner is the victim of this, shot and on his way to the hospital in an ambulance in the episode's opening instead of piloting his Corvette.
Silliphant's story elegantly ends the flashback and returns to the present for some strong plot twists and a resolution of the drama that underscores the series' overall theme of escaping from confinement and searching for self, in this case represented by the spirit of jazz.