Deadly Weapons is a 1973 movie melodrama directed by Doris Wishman, starring Chesty Morgan and Harry Reems. It was written by Judy J. Kushner (Wishman's niece).

Warning: Wikipedia contains spoilers

Morgan, a woman whose bust is 73 inches, plays Crystal, a successful advertising executive who tracks down the men who killed her lover. One by one, she seduces each man, renders him weak and groggy with a laced drink, and then smothers him to death with her monstrous breasts.

When she attacks her victims, her enormous cleavage swallows their heads whole and their muffled screams are answered only be her cruel laughter. Twisting and turning for air, her victims' helpless struggling accomplishes little, other than to cause Crystal's "weapons" to jiggle and shimmy until the execution is accomplished.

This is one of two films Doris Wishman made with Chesty Morgan, the other is Agent 73.