Murder follows an axe murderer home when she's released from a mental hospital.

Lucy Harbin returns unexpectedly to her farm after a trip out of town and discovers her husband in bed with another woman. Crazed, she grabs an ax and hacks the lovers to death in full view of her 3-year-old daughter, Carol. Lucy is committed to an asylum and her brother and sister-in-law take Carol and move west to another farm. Twenty years later Lucy is released from the asylum and comes to find her family. Carol, now a talented sculptress, is in love with wealthy young Michael Fields. The girl is anxious for her dowdy mother to look as she did 20 years earlier and persuades her to wear makeup, a black wig, youthful clothing, and jangling jewelry. Lucy behaves badly when she meets Michael; and the arrival of Dr. Anderson, the psychiatrist who treated her at the asylum, upsets her further. The doctor tells Carol that he thinks Lucy should return to the asylum and he is about to tell Lucy when he is hacked to death in a farm building. Later, Lucy tells Carol that the doctor left, but the girl finds the doctor's car and, suspecting that Lucy has reverted to violence, she hides the car. A hired hand sees her, and the next day Carol finds him repainting the car, which he says is his. She fires him but he refuses to leave, threatening to reveal that he discovered Dr. Anderson's body in the meat refrigerator. Lucy overhears the conversation, and the hired hand is later found axed to death. That night Lucy meets Michael's parents and she nervously reveals the couple's plan to wed. Mrs. Fields objects and is rude to Lucy, who flies into a rage, vows that nothing will stop the marriage, and rushes from the house. Later that night, Mr. Fields is chopped to death and, when his wife investigates the noise, a woman who appears to be Lucy attempts to kill her, but Lucy walks in and stops her. The look-alikes grapple until Lucy strips a mask and wig from the other woman, revealing her own daughter, who had planned the deaths of her beau's parents even before Lucy's release. Carol has a complete breakdown and is committed to an asylum. Realizing that her own crime led to Carol's insanity, Lucy goes to care for her at the asylum.