In the previous film in the series, THE SECRET OF DR. KILDARE, the good doctor is practicing well outside his area of expertise. Despite being a diagnostician, he performed like a trained psychiatrist and since it was a Hollywood movie, everything worked out in the end! Well, once again, Kildare behaves as if he's a well-trained psychiatrist AND he does very risky and dangerous work using insulin therapy--a type of therapy with dubious effectiveness.
Now the logic of this film is completely absent--but the film is still quite watchable due to the excellent acting and characters. In fact, this was a trademark of the Kildare series--excellent cast but occasionally goofy stories.