The tone, lighting, and the uncertainty which grips Paula ratchets up the intensity of Gaslight, making the potential for some terrible outcome ever present. Gaslight is a visually expressive film, with long shadows and identifiable silhouettes cast by the light of the gas lamps, characteristics of the emerging film noir style. The effect is that it creates an ominous visual cue, suggesting an evil at work when the lights dim.

The film draws its name from the eponymous gas light which dims in the house as Paula begins to hear sounds above her room when she is alone, manifestations she attributes to hallucinations. Gaslight is set roughly at the turn of the 20th century, prior to the introduction of widespread electricity in cities and other technological advances. His malevolence manifests like a creeping insidiousness over the course of the film, like a vice squeezing tighter and tighter, turning sweet to sour by degrees. What appears early on as mere romantic obsession when Gregory shows up in Cornwall to meet Paula, after she indicated she needed time to think on his proposal, is in reality a control strategy. These kind of people cut off their victims from outside contact, both to prevent them from revealing the abuser's tactics but also to make them solely dependent on people like them. This disintegration of personality, allowing for the victimizer to establish themselves as the sole possessor of power in a social dynamic, is a psychological weapon used by leaders of cults and politicians, but also abusive lovers. She is turned into a quivering shell of herself, terrified of leaving her house and to having company-which is just how Gregory wants it. What Paula becomes by the end of Gaslight is a far cry from the confident, recovered young woman at the beginning. And Gregory is power hungry over Paula, manipulating events so that she is made to be humiliated in public or in front of the servants, breaking down her self-esteem and granting Gregory the power to sink his talons deeper. Why conceal this fact? One suspects that it was Gregory's idea-after all, the more secrets one can keep, the more power they have over someone. Interestingly, even our first introduction to him is a kind of deception Paula has confessed to her singing instructor that she is in love, but it isn't until she leaves that we learn that it was the same pianist who was working with Paula's teacher all along. Even though Gregory's motivations are concealed through much of Gaslight, hints teased here and there for our benefit, it is enough to despise him because we see just how charming and suave he is from the start, and how he transforms into a cruel, abusive tyrant. Paula is more sympathetic by virtue of Gregory's disregard for the sacred bond of marriage, as it becomes more apparent that his interests in marrying Paula were to achieve a far more profitable result. Gaslight is a fascinating character study not just of the young woman set upon by a domineering husband into becoming a skittish wreck, convinced she's losing her mind, but of the venomous husband, who tells different stories to different audiences, composing tunes to have those around him dance to his song. In the case of Paula, it become clear with time that Gregory is the victimizer. The term 'gaslighting' comes from this film, and is used to describe the psychological abuse which comes from a person being mentally tormented by another into doubting their sanity.

Gaslight 1944