Movies like this one are the reasons Criterion Collection is so fabulous: here's a b-grade exploitation film that turned out light years better than it needed to be with excellent performances (Shirley Stoler where are you?… what? Pee Wee's Playhouse?); sophisticated filmmaking despite a small budget; and a cutting edge plot featuring serial killers as protagonists.
This movie can't get out from under the weight of its low budget completely and it seems almost like an industrial film at times–to its advantage–and even Criterion couldn't do much of anything with the terrible audio, I recommend watching with subtitles.
The story is based on the true life drama of two outsiders, Martha Beck and Ray Fernandez who fell in love, swindled widows out of their money, and sometimes killed them too. They were executed in 1951 for their crimes.
Scorsese was initially set to direct, but the honor went instead to Lawrence Kastle, and he did an amazing job. Really a masterpiece that predates Taxi Driver and the less thanstellar Henry: Portrait of a Serial Killer. But even masterpieces can't always be for everyone.
If you look for a positive outlook on humanity in your films, I would steer clear. This is one nasty, cruel little movie, about nasty cruel people, so don't let the campiness of the poster fool you. No one comes out looking good in this film. Even the victims. And by the time one of them does evoke our sympathy, we witness her moment of realization that she's going to die with an unflinching, seemingly unending closeup of her terrified eyes. It's rough stuff and way ahead of its time. Also worth noting is the interesting soundtrack with music by Gustav Mahler.