"The Dark File" by Irving Wallace is certainly not up to the level of his best-selling novels like "The Chapman Report" or "The Prize", and is stillborn on "Alcoa Theatre". It does provide a couple of dramatic roles for its talented leading ladies.
Kim Hunter is especially adept at portraying the heavy, a scheming woman who actually engenders sympathy at the very end. She spends the show manipulating, a true homewrecker you can love to hate. Yet her performance is subtle, not barnstorming at all.
Her husband, a psychiatrist, has just died, and the man she really loves (woodenly played by Lyn McCarthy, miscast) is the psychiatrist taking over her husband's practice and is about to marry Patricia Breslin. Going through her late husband's files, to help transfer them to Lyn, she finds Pat's file as a patient, and in flashback from the file we see how troubled Breslin was to get married but her groom died, and she ended up giving away the baby.
In idle conversation, Kim mentions how her spouse would often talk to her about cases, never mentioning any names, and she uses Pat's case as an example. Pat thinks it's a coincidence and tries to play dumb, but Kim schemes to get her into trouble with Lyn and it looks like their marriage is off. The plot contrivances are not very believable, but the story ends with issues tied up neatly and a strong, ironic ending.
Casting McCarthy ruins the show, as he is the usual wimp chosen for leading man precisely not to distract from the strong female characters. The story needed the balancing premise of a solid male character (whose affections both women were vying for), say an actor with an edge like a Gig Young or George Grizzard.