In his memoirs "The Garner Files" (2011), James Garner rated this as his worst movie. His comment about it: "I'd summarize the plot, but to this day, I have no clue what it is. Worst picture I ever made. What where they thinking? What was I thinking?" (page 256).
MGM purchased the rights to Evan Hunter's novel at the galley proof stage for two hundred thousand dollars.
The exterior of the "hospital" that Garner rushes to near the end of the film is actually the rear entrance to the Thalberg executive office building on the old M-G-M lot in Culver City.
Filmed in New York City. Locations include Washington Square, Central Park, Greenwich Village, New York University, Shubert Alley, Plaza Hotel, and the Queensboro Bridge.