Ms .45 (also known as Angel of Vengeance or Ms. 45) is a 1981 American exploitation thriller film directed by Abel Ferrara and starring Zoë Tamerlis.

[5] While walking home from work, Thana,[a] a mute seamstress in New York City's Garment District, is raped at gunpoint in an alley by a masked attacker.

Thana strikes this second assailant with a small glass apple, then bludgeons him to death with an iron, before carrying his body to the bathtub.

The next day at work, Thana goes into shock after watching her boss Albert rip a shirt off a mannequin, which worries her co-workers.

After cleaning her bathtub, she decides to take a shower, but as she strips, she hallucinates the first attacker in the mirror grabbing her breast, horrifying her.

As the limbs start to attract the attention of the media, Albert brings Thana into his office and invites her to a Halloween party that he is throwing for work, telling her that there will be "many boys there [her] age" while stroking her neck.

As her quest of vengeance increases, Thana starts regularly targeting and killing several men, including an arrogant fashion photographer, a pimp who assaults a prostitute, several members of a gang seeking to sexually assault her, a Saudi Arabian businessman and his limousine driver, and even drives a recently dumped salesman to suicide after her gun jams.

The party stops and her co-workers run upstairs to Thana, but quickly realize that she is the murderer when she steps out of the room with her pistol.

Abel Ferrara first received the script to Ms .45 in the mail from Nicholas St. John, who scribed the director's previous film, The Driller Killer.

While Ferrara has claimed he instantly loved the idea and didn't change a thing from what was sent to him, cinematographer James Lemmo noted that the script itself was rather thin, and screenwriter St. John would occasionally add dialogue as shooting continued.

[12] In the sixth episode of the HBO teen drama Euphoria's first season, the character Kat Hernandez, portrayed by Barbie Ferreira, dresses up as Thana for Halloween.