In some ways, the biggest problem with this film is the script's portrayal of Chris Claybourne, whose switch from debauched playboy to dedicated researcher seems almost too abrupt. Sure, the deterioration of his relationship with Rita plays a part in the character's change, as does seeing colleagues die in South America. But, he also goes from heartsick juvenile to bitter old man with the flip of a switch. As a result, it's really hard to get a handle on Chris. The prior year, Taylor had become very much a matinee idol in Magnificent Obsession and one wonders if the writers were trying to capitalize on the popularity of that film, by making Chris similar to Robert Merrick. In this New York Times review, the popularity of Mr. Taylor (following his success in Magnificent Obsession) figures heavily in the commentary.
At one point, (according to the AFI Catalog), Jean Harlow and Clark Gable were being considered for the lead roles in this film; later, it was reported that the cast included Harlow and Franchot Tone. However, it was already public knowledge that Stanwyck and Taylor were dating (see this TCM article for more about the film); assumedly, that contributed greatly to casting Stanwyck rather than Harlow. Harlow in the role of Rita would have been very different, as Stanwyck gives Rita an elegance and strength that makes her attractive and likeable. Given Rita's actions later in the film, it could be hard to retain sympathy for her, but Stanwyck has the skill to make Rita much more sinned against than sinning.
Another handicap is John Eldredge as Thomas Claybourne, Jr. Simply put, he's a blackmailer, a liar, and a weakling. Surely, one doesn't sympathize much with Chris' proclivity for gambling and then writing bad checks. But Tom's carping about the lack of money available when he is standing in a house that could house 30 people rather than 3 seems just reprehensible. And, on top of that, to then elope with the woman his brother wanted to marry - a woman he all but called a whore, is just despicable. One wonders why Chris doesn't deck him when he returns from South America.
Joh Eldredge never seemed to get beyond second banana status, and given his performance here, it's understandable. The scenes in which he tells his brother about his passion for Rita are over-the-top and rather insincere. He had a respectable film career; then moved into television in his later years. In fact, he worked up until his death of a heart attack in 1961. Growing up, I remember him clearly as a frequent Superman villain in The Adventures of Superman.
The costuming is good - Stanwyck has some nice outfits, but by and large, the actors look like they've been dipped in Clorox in the jungle scenes - everyone in white, and not a stain to be seen. And we, as mentioned, had some problems with the set used as the Claybourne home. It makes it awfully hard to believe there are any financial constraints within the family.
Jean Hersholt as Professor Pop Fahrenheim, Chris' supervisor and mentor on the expedition, is very good, as usual. He is able to provide an amount of gravitas to that role, without making him pious. However, Samuel S. Hinds as Dr. Thomas Claybourne, Sr. is totally wasted. He has, perhaps two scenes, and does little except worry about Tom, Jr.
Some amount of the film concentrates on the aspect of heroic medicine, which is very reminiscent of Arrowsmith. Of course, in 1936, vaccines were a relatively new concept, and there is a convention in films of this era that the noble physicians (Pop and Thomas, Sr. - who is pouring all his money back into his hospital) are willing to sacrifice their very lives to save mankind. Chris' father wants Chris to become that kind of physician. That Chris is eager to risk himself to prove the efficacy of his vaccine shows the growth of the character, and that he has indeed become ennobled by his work in the tropics. In this day and age of controlled clinical trials, and IRBs (institutional review boards that verify that studies are both necessary and will minimize harm), this method of medical research seems outlandish. But take a look at this brief article on Joseph Goldberger - it was the way of the world at that time.
We will leave you with this trailer from the film. Next time, we'll be looking at an early movie about the medical profession.