Millar's books are distinguished by depth of characterization. Often we are shown the rather complex interior lives of the people in her books, with issues of class, insecurity, failed ambitions, loneliness or
existential isolation or paranoia often being explored. Unusual people, mild societal misfits or people who don't quite fit into their surroundings are given much interior detail. In some of the books (for example in
The Iron Gates) we are given insight into what it feels like to be losing touch with reality and evolving into madness. In general, she is a writer of both expressive description and economy, often ambitious in conveying the sociological context of the stories. Millar often delivers "surprise endings," but the details that would allow the solution of the surprise have usually been subtly included. Her books focus on subtleties of human interaction and rich psychological detail of individual characters as much as on plot. Millar was a pioneer in writing about the psychology of women. She wrote about class distinctions, sexual freedom and frustration, and the ambivalence of moral codes depending on a character's economic circumstances. Read against the backdrop of Production Code-era movies of the time, her novels show the reader a different morality than what was portrayed in Hollywood during the 40's and 50's. It has been argued that Millar "essentially created a new hybrid form of literature: detective literature" in contrast to formulaic genre stories. Many websites cite her as working as a screenwriter for
Warner Brothers just after
World War II, but no further details are given as to what she may have worked on, even on
imdb.com. Around that time, Warners bought the option on her novel
The Iron Gates, with its portrait of a woman descending into madness, but reportedly
Bette Davis and other prominent Warner Brothers actresses ultimately turned it down because the memorable protagonist is missing for the last third of the story. The film was never produced. In the early '60s, two of her novels were adapted for the anthology TV series
Alfred Hitchcock Presents and
Thriller.:
Beast in View and ''Rose's Last Summer,'' which starred
Mary Astor. While she was not known for any one recurring detective (unlike her husband, whose constant gumshoe was Lew Archer), she occasionally used a detective character for more than one novel. Among her occasional ongoing sleuths were Canadians Dr. Paul Prye (her first invention, in the earliest books) and Inspector Sands (a quiet, unassuming Canadian police inspector who might be the most endearing of her recurring inventions). In the California years, a few books featured either Joe Quinn, a rather down-on-his-luck private eye, or Tom Aragon, a young,
Hispanic lawyer. Most of Millar's books are still in print in America. Starting in 2016, Soho Syndicate has published a large selection of omnibus re-issues grouped by theme. Many are available as single ebooks. ==Awards and recognition==