The title sequence with a giant looming woman over NYC gives a preview of the gravity of the unfolding story.
Torch singer Sheila Bennett (Keyes) returns to New York from Cuba, she arrives at Pennsylvania Station carrying $50,000 worth of smuggled diamonds, she is also carrying smallpox, which could start a devastating and quickly spreading epidemic in the unprotected city. Why she is not arriving by boat or plane may be due to the fact that she knows she is being tailed by custom agents. Upon arrival at Penn she immediately calls her husband (Korvin) who is her partner in the diamond smuggling racket. She tells him that she has as a precaution mailed the smuggled diamonds to their apartment in Brooklyn
Sheila (Keyes) in a phone booth at Penn Station.
Her slimey husband (Korvin) who is doing her sister while she is away
Sheila is not feeling well she has headaches and back pains and re-occurring fevers. She finds a clinic off Times Square on the way to Brooklyn and there meets nurse (Malone) and Doctor Wood (Bishop). They misdiagnose her with the flu and Dr. Wood gives her some medicine to take. Before Sheila leaves the clinic she gives a small girl a decorative pin, contact with the pin infects the child, Sheila is a walking death spreader. The child soon comes down with the symptoms and other victims begin to show up sick. Smallpox is diagnosed and now Sheila is hunted by Custom agent Johnson while Public Health doctor Wood searches in vain for the unknown person spreading the deadly disease far and wide.
Nurse (Malone) and Dr. Wood (Bishop)
Arriving at her apartment in Brooklyn sheila finds her baby sister (Albright) there with her Husband. Albright has fallen for Sheila's Husband and is carrying on an affair with him, but the increasingly ill Sheila is at first too sick to notice. Meanwhile Custom agent Johnson loses her but keeps doggedly on the trail; while Public Health doctor Wood searches the areas where victims are turning up.
Sheila finds out from the landlady that her husband is double crossing her and is screwing her sister, and now she becomes obsessed with finding her faithless husband Matt, who plans to abscond with the diamonds. Sheila finds out from the crooked jeweler they are in cahoots with that Matt will be back in ten days with the diamonds the medicine and her determination to get Matt is keeping her alive. Sheila flees to her brothers flop house "the Moon" and hides out there.
Sheila's Brother (Whit Bissell)
Sheila back at the clinic confronting Dr. wood
The finale at the jewlers
This is an OK thriller, though it does beg the question about what happened to all the other contacts Sheila made before she hit NYC, the people on the boat or plane she most assuredly came in contact with before she took the train. Unless she was somehow not contagious during some type of incubation period, but what do i know. This film has great location shots of old Penn Station, various Manhattan locals and a great 3rd Avenue el sequence that I've captured and uploaded on Youtube here: