At first glance the femme fatale role appears to be one of great power, a fact punctuated well by the role of Phyllis Dietrichson in Double Indemnity. Here is a woman who has great influence over the people who surround her, specifically the upstanding insurance salesman, Walter Neff. This power could be construed as a positive step for the portrayal of women on screen, but a deeper look proves this to be quite the contrary. The power of Phyllis in the film comes across more as a force. The characters who cross her path can either resist this force or surrender to it. In the reading by Lott, he says that, as is the case with Walter, the men often fall prey to these women thereby capitulating to the "darkness" they represent.
The "right" and "wrong" are identified rather quickly in Double Indemnity. The "right" choice for Walter would be to take the job as Keyes' assistant. The job is a paycut, but an honorable pursuit of truth and justice. And the "wrong" way is to follow Phyllis down a path of greed, betrayal and murder. Neff's fall is hard and fast. While both are punished in the end for their choices, Phyllis, as the femme fatale must lose her life and her power. In this case, Neff has fallen under the spell of the innocent Lola. He betrays Phyllis for her.
Ultimately, The femme fatale is an embodiment of the male fear of a woman's power. Therefore, the only power a woman can have in this type of film is one of that is sexual, immoral and corrupt, making her in general an unlikable character.