Special effects: Although almost the entire film is in black and white, the tidal wave sequence towards the end is shown in green tint, and the final shot of the completed portrait of Jennie is in full Technicolor. The original theatrical releases in Los Angeles (Carthay Circle Theatre), New York (Rivoli Theatre) and Boston (Esquire & Mayflower Theatres) presented the tidal wave sequence in Magnascope on the Cycloramic screen with Multi-Sound. The Cycloramic screen was claimed to be more reflective than regular screens with no distortion visible from any seat in the theatre, Multi-Sound was an early version of a Surround Sound-type speaker installation. Bosley Crowther, film critic for the New York Times, described it as "a howling hurricane that will blast you out of your seat."
Bernard Herrmann was hired to write an original background score and did compose several themes but due to various production delays as well as the fact that Herrmann was tiring of David O. Selznick's demands, he dropped out and was replaced by Dimitri Tiomkin who, at the insistence of Selznick, ended up using themes by Claude Debussy. At the time Tiomkin was condemned by his colleagues for his adaptations. All that remains of Herrmann's contribution is the haunting song sung by Jennie entitled "Where I Come From, Nobody Knows".
Producer David O. Selznick initially considered filming this movie over a period of several years, casting a young actress in the role of Jennie and shooting portions of the film over time as the actress actually grew older in real life. (Shirley Temple, then under contract to Selznick, was reportedly intended for the role, had the movie been filmed that way.) In the end, however, Selznick abandoned the idea as too risky and difficult to film properly.
The portrait of Jennie supposedly painted by Joseph Cotten's character, Eben Adams, was in reality created by noted portrait artist Robert Brackman. Jennifer Jones came in for more than a dozen sittings in Brackman's Connecticut studio. Actually Robert Brackman was obliged to paint not only one but two Portraits of Jennie as the first one (a "lush, opulent" one as the artist told to this writer personally) was scrapped after script changes necessitated a completely new and more simple one (that appears in the film). A black-and-white photo of this version can be seen in one of the books on Brackman.
After the film flopped at the box-office, the film was re-released under the title "Tidal Wave" in 1950, marketing it to a different audience in the hopes of making a profit. The re-release also flopped.
David Wayne and Albert Sharpe, who both have supporting roles in this film, were the stars of the original stage production of "Finian's Rainbow". That play opened on Broadway the year before this film was released and was playing there at the same time this film was being made.
This was cinematographer Joseph H. August's last film. He died in late 1947 from a heart attack before the long and tumultuous production was completed, and was posthumously nominated for an Academy Award for Best Black & White Cinematography in 1949. Lee Garmes finished shooting the film, uncredited.