Plot
Artist Patience Phillips works for the cosmetics company Hedare Beauty, which is ready to ship a new skin cream called Beau-line that is able to reverse the effects of aging.
Patience visits the R&D laboratory facility to deliver a revised ad design. She overhears a discussion between scientist Dr. Ivan Slavicky and Laurel Hedare, the wife of company-owner George Hedare, about the dangerous side effects from continual use of the product. Laurel's guards discover Patience and are ordered to dispose of her.
Patience tries to escape using a conduit pipe, but it is soon sealed off by the guards, who flush the pipe with water. Left for dead she washed up on shore, Patience is mysteriously revived by the Egyptian Mau cat Midnight, which had appeared at her apartment earlier. From that moment on, she develops cat-like metahuman attributes. From Midnight's owner, eccentric researcher Ophelia Powers, Patience learns that Egyptian Mau cats serve as messengers of the goddess Bast. Patience realizes that she is now a "Catwoman", reborn with abilities that are both a blessing and a curse that turn her away from her former meek people-pleasing qualities.
While at home, Patience is annoyed by the ruckus caused by her neighbor's party and lashes out by spraying the amplifiers with water to mute the noise. She disguises herself as a mysterious vigilante named Catwoman to hide her identity, then, under the cover of darkness, searches for answers about what led to her supposed death and subsequent framing for the murder of Slavicky, who she discovers was killed. When Patience confronts George (who is attending an opera with another woman) as Catwoman, he reveals that he knows nothing about the side effects.
The police, led by Patience's love interest, detective Tom Lone, arrive, and Catwoman escapes. Later on, Laurel murders George for his growing suspicions and infidelity and admits to having Dr. Slavicky killed because he wanted to cancel the product's release. She contacts Catwoman and frames her for the murder, planning to release Beau-line to the public the following day. Tom then takes Catwoman into custody.
Patience slips out of her cell and confronts Laurel in her office, rescuing Tom, who came to question Laurel after second thoughts about Patience's guilt, in the process, and revealing that Laurel is the one responsible for her death. As they fight, Patience sees she is unable to hurt Laurel.
Laurel reveals the product's side effects: discontinuing its use makes the skin disintegrate, while continuing its use makes the skin as hard as marble and the user impervious to pain. During the fight, Patience scratches Laurel's face several times, causing her to fall out of a window and grab onto a broken glass pipe. Laurel sees her rapidly disfiguring face in a window's reflection. Horrified, she fails to grab hold of Patience's outstretched hand and falls to her death.
Although Patience is cleared of any charges made against her regarding the deaths of Dr. Slavicky and the Hedares, she decides to end her relationship with Tom so as to continue living outside the law and enjoy her newfound freedom as Catwoman.